Add different timeout scenarios to Process.checkHealthEndpoint #276 (#278)

- add a TCP connection timeout of 500ms
- increase HTTP client timeout to 5000ms

In this new behaviour the upstream has 500ms to accept a tcp connection
and 5000ms to respond to the HTTP request.

.github/ISSUE_TEMPLATE/bug-report.md

@@ -1,11 +1,13 @@
 ---
 name: Bug Report
-about: Something is not working as expected...
+about: I found a defect
 title: ''
-labels: bug
+labels: 'unconfirmed bug'
 assignees: ''
 
 ---
+> [!IMPORTANT]
+> If you have questions about llama-swap please post in the Q&A in Discussions. Use bug reports when you've found a defect and wish to discuss a fix.
 
 **Describe the bug**
 A clear and concise description of what the bug is.

.github/workflows/go-ci.yml

@@ -22,6 +22,13 @@ jobs:
       with:
         go-version: '1.23'
 
+    # Only run in this linux based runner
+    - name: Check Formatting
+      run: |
+        if [ "$(gofmt -l . | grep -v 'event/.*_test.go' | wc -l)" -gt 0 ]; then
+          gofmt -l . | grep -v 'event/.*_test.go'
+          exit 1
+        fi
     # cache simple-responder to save the build time
     - name: Restore Simple Responder
       id: restore-simple-responder

.github/workflows/release.yml

@@ -7,6 +7,10 @@ on:
 
   # Allows manual triggering of the workflow
   workflow_dispatch:
+    inputs:
+      tag:
+        description: 'Tag version to release (e.g. v144)'
+        required: true
 
 permissions:
   contents: write
@@ -20,15 +24,15 @@ jobs:
         uses: actions/checkout@v4
         with:
           fetch-depth: 0
+          ref: ${{ github.event.inputs.tag || github.ref }}
       -
         name: Set up Go
         uses: actions/setup-go@v5
-
       -
         name: Set up Node.js
         uses: actions/setup-node@v4
         with:
-          node-version: '23'  # or your preferred version
+          node-version: '23'
       -
         name: Install dependencies and build UI
         run: |
@@ -46,4 +50,30 @@ jobs:
           version: '~> v2'
           args: release --clean
         env:
-          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+  trigger-tap-update:
+    runs-on: ubuntu-latest
+    needs: goreleaser
+    steps:
+      - name: "Resolve tag to dispatch"
+        id: tag
+        run: |
+          if [[ "${{ github.event_name }}" == "workflow_dispatch" ]]; then
+            echo "tag=${{ github.event.inputs.tag }}" >> "$GITHUB_OUTPUT"
+          else
+            echo "tag=${{ github.ref_name }}" >> "$GITHUB_OUTPUT"
+          fi
+
+      - name: "Trigger tap repository update"
+        uses: peter-evans/repository-dispatch@v2
+        with:
+          token: ${{ secrets.TAP_REPO_PAT }}
+          repository: mostlygeek/homebrew-llama-swap
+          event-type: new-release
+          client-payload: |
+            {
+              "release": {
+                "tag_name": "${{ steps.tag.outputs.tag }}"
+              }
+            }

.gitignore

@@ -4,3 +4,4 @@ build/
 dist/
 .vscode
 .DS_Store
+.dev/

Makefile

@@ -45,6 +45,7 @@ mac: ui
 linux: ui
 	@echo "Building Linux binary..."
 	GOOS=linux GOARCH=amd64 go build -ldflags="-X main.commit=${GIT_HASH} -X main.version=local_${GIT_HASH} -X main.date=${BUILD_DATE}" -o $(BUILD_DIR)/$(APP_NAME)-linux-amd64
+	GOOS=linux GOARCH=arm64 go build -ldflags="-X main.commit=${GIT_HASH} -X main.version=local_${GIT_HASH} -X main.date=${BUILD_DATE}" -o $(BUILD_DIR)/$(APP_NAME)-linux-arm64
 
 # Build Windows binary
 windows: ui

README.md

@@ -18,32 +18,37 @@ Written in golang, it is very easy to install (single binary with no dependencie
   - `v1/completions`
   - `v1/chat/completions`
   - `v1/embeddings`
-  - `v1/rerank`
   - `v1/audio/speech` ([#36](https://github.com/mostlygeek/llama-swap/issues/36))
   - `v1/audio/transcriptions` ([docs](https://github.com/mostlygeek/llama-swap/issues/41#issuecomment-2722637867))
+- ✅ llama-server (llama.cpp) supported endpoints:
+  - `v1/rerank`, `v1/reranking`, `/rerank`
+  - `/infill` - for code infilling
+  - `/completion` - for completion endpoint
 - ✅ llama-swap custom API endpoints
   - `/ui` - web UI
   - `/log` - remote log monitoring
   - `/upstream/:model_id` - direct access to upstream HTTP server ([demo](https://github.com/mostlygeek/llama-swap/pull/31))
   - `/unload` - manually unload running models ([#58](https://github.com/mostlygeek/llama-swap/issues/58))
   - `/running` - list currently running models ([#61](https://github.com/mostlygeek/llama-swap/issues/61))
+  - `/health` - just returns "OK"
 - ✅ Run multiple models at once with `Groups` ([#107](https://github.com/mostlygeek/llama-swap/issues/107))
 - ✅ Automatic unloading of models after timeout by setting a `ttl`
 - ✅ Use any local OpenAI compatible server (llama.cpp, vllm, tabbyAPI, etc)
-- ✅ Docker and Podman support
+- ✅ Reliable Docker and Podman support with `cmdStart` and `cmdStop`
 - ✅ Full control over server settings per model
+- ✅ Preload models on startup with `hooks` ([#235](https://github.com/mostlygeek/llama-swap/pull/235))
 
 ## How does llama-swap work?
 
-When a request is made to an OpenAI compatible endpoint, lama-swap will extract the `model` value and load the appropriate server configuration to serve it. If the wrong upstream server is running, it will be replaced with the correct one. This is where the "swap" part comes in. The upstream server is automatically swapped to the correct one to serve the request.
+When a request is made to an OpenAI compatible endpoint, llama-swap will extract the `model` value and load the appropriate server configuration to serve it. If the wrong upstream server is running, it will be replaced with the correct one. This is where the "swap" part comes in. The upstream server is automatically swapped to the correct one to serve the request.
 
 In the most basic configuration llama-swap handles one model at a time. For more advanced use cases, the `groups` feature allows multiple models to be loaded at the same time. You have complete control over how your system resources are used.
 
 ## config.yaml
 
-llama-swap is managed entirely through a yaml configuration file. 
+llama-swap is managed entirely through a yaml configuration file.
 
-It can be very minimal to start: 
+It can be very minimal to start:
 
 ```yaml
 models:
@@ -54,7 +59,7 @@ models:
       --port ${PORT}
 ```
 
-However, there are many more capabilities that llama-swap supports: 
+However, there are many more capabilities that llama-swap supports:
 
 - `groups` to run multiple models at once
 - `ttl` to automatically unload models
@@ -70,13 +75,26 @@ See the [configuration documentation](https://github.com/mostlygeek/llama-swap/w
 
 ## Web UI
 
-llama-swap ships with a web based interface to make it easier to monitor logs and check the status of models. 
+llama-swap includes a real time web interface for monitoring logs and models:
 
-<img width="1758" alt="image" src="https://github.com/user-attachments/assets/31ae5bcd-5efd-46b0-b64b-6db9e60196d3" />
+<img width="1360" height="963" alt="image" src="https://github.com/user-attachments/assets/adef4a8e-de0b-49db-885a-8f6dedae6799" />
 
-## Docker Install ([download images](https://github.com/mostlygeek/llama-swap/pkgs/container/llama-swap))
+The Activity Page shows recent requests:
 
-Docker is the quickest way to try out llama-swap:
+<img width="1360" height="963" alt="image" src="https://github.com/user-attachments/assets/5f3edee6-d03a-4ae5-ae06-b20ac1f135bd" />
+
+## Installation
+
+llama-swap can be installed in multiple ways
+
+1. Docker
+2. Homebrew (OSX and Linux)
+3. From release binaries
+4. From source
+
+### Docker Install ([download images](https://github.com/mostlygeek/llama-swap/pkgs/container/llama-swap))
+
+Docker images with llama-swap and llama-server are built nightly.
 
 ```shell
 # use CPU inference comes with the example config above
@@ -98,7 +116,7 @@ $ curl -s http://localhost:9292/v1/chat/completions \
 ```
 
 <details>
-<summary>Docker images are built nightly for cuda, intel, vulcan, etc ...</summary>
+<summary>Docker images are built nightly with llama-server for cuda, intel, vulcan and musa.</summary>
 
 They include:
 
@@ -121,9 +139,23 @@ $ docker run -it --rm --runtime nvidia -p 9292:8080 \
 
 </details>
 
-## Bare metal Install ([download](https://github.com/mostlygeek/llama-swap/releases))
+### Homebrew Install (macOS/Linux)
 
-Pre-built binaries are available for Linux, Mac, Windows and FreeBSD. These are automatically published and are likely a few hours ahead of the docker releases. The baremetal install works with any OpenAI compatible server, not just llama-server.
+The latest release of `llama-swap` can be installed via [Homebrew](https://brew.sh).
+
+```shell
+# Set up tap and install formula
+brew tap mostlygeek/llama-swap
+brew install llama-swap
+# Run llama-swap
+llama-swap --config path/to/config.yaml --listen localhost:8080
+```
+
+This will install the `llama-swap` binary and make it available in your path. See the [configuration documentation](https://github.com/mostlygeek/llama-swap/wiki/Configuration)
+
+### Pre-built Binaries ([download](https://github.com/mostlygeek/llama-swap/releases))
+
+Binaries are available for Linux, Mac, Windows and FreeBSD. These are automatically published and are likely a few hours ahead of the docker releases. The binary install works with any OpenAI compatible server, not just llama-server.
 
 1. Download a [release](https://github.com/mostlygeek/llama-swap/releases) appropriate for your OS and architecture.
 1. Create a configuration file, see the [configuration documentation](https://github.com/mostlygeek/llama-swap/wiki/Configuration).
@@ -137,7 +169,7 @@ Pre-built binaries are available for Linux, Mac, Windows and FreeBSD. These are
 ### Building from source
 
 1. Build requires golang and nodejs for the user interface.
-1. `git clone git@github.com:mostlygeek/llama-swap.git`
+1. `git clone https://github.com/mostlygeek/llama-swap.git`
 1. `make clean all`
 1. Binaries will be in `build/` subdirectory
 

config.example.yaml

@@ -1,9 +1,17 @@
 # llama-swap YAML configuration example
 # -------------------------------------
 #
+# 💡 Tip - Use an LLM with this file!
+# ====================================
+#  This example configuration is written to be LLM friendly. Try
+#  copying this file into an LLM and asking it to explain or generate
+#  sections for you.
+# ====================================
+
+# Usage notes:
 # - Below are all the available configuration options for llama-swap.
-# - Settings with a default value, or noted as optional can be omitted.
-# - Settings that are marked required must be in your configuration file
+# - Settings noted as "required" must be in your configuration file
+# - Settings noted as "optional" can be omitted
 
 # healthCheckTimeout: number of seconds to wait for a model to be ready to serve requests
 # - optional, default: 120
@@ -15,15 +23,21 @@ healthCheckTimeout: 500
 # - Valid log levels: debug, info, warn, error
 logLevel: info
 
+# metricsMaxInMemory: maximum number of metrics to keep in memory
+# - optional, default: 1000
+# - controls how many metrics are stored in memory before older ones are discarded
+# - useful for limiting memory usage when processing large volumes of metrics
+metricsMaxInMemory: 1000
+
 # startPort: sets the starting port number for the automatic ${PORT} macro.
 # - optional, default: 5800
 # - the ${PORT} macro can be used in model.cmd and model.proxy settings
 # - it is automatically incremented for every model that uses it
 startPort: 10001
 
-# macros: sets a dictionary of string:string pairs
+# macros: a dictionary of string substitutions
 # - optional, default: empty dictionary
-# - these are reusable snippets
+# - macros are reusable snippets
 # - used in a model's cmd, cmdStop, proxy and checkEndpoint
 # - useful for reducing common configuration settings
 macros:
@@ -86,44 +100,55 @@ models:
 
     # checkEndpoint: URL path to check if the server is ready
     # - optional, default: /health
-    # - use "none" to skip endpoint ready checking
     # - endpoint is expected to return an HTTP 200 response
-    # - all requests wait until the endpoint is ready (or fails)
+    # - all requests wait until the endpoint is ready or fails
+    # - use "none" to skip endpoint health checking
     checkEndpoint: /custom-endpoint
 
-    # ttl: automatically unload the model after this many seconds
+    # ttl: automatically unload the model after ttl seconds
     # - optional, default: 0
     # - ttl values must be a value greater than 0
     # - a value of 0 disables automatic unloading of the model
     ttl: 60
 
-    # useModelName: overrides the model name that is sent to upstream server
+    # useModelName: override the model name that is sent to upstream server
     # - optional, default: ""
-    # - useful when the upstream server expects a specific model name or format
+    # - useful for when the upstream server expects a specific model name that
+    #   is different from the model's ID
     useModelName: "qwen:qwq"
 
     # filters: a dictionary of filter settings
     # - optional, default: empty dictionary
+    # - only strip_params is currently supported
     filters:
       # strip_params: a comma separated list of parameters to remove from the request
       # - optional, default: ""
-      # - useful for preventing overriding of default server params by requests
-      # - `model` parameter is never removed
+      # - useful for server side enforcement of sampling parameters
+      # - the `model` parameter can never be removed
       # - can be any JSON key in the request body
       # - recommended to stick to sampling parameters
       strip_params: "temperature, top_p, top_k"
 
+    # concurrencyLimit: overrides the allowed number of active parallel requests to a model
+    # - optional, default: 0
+    # - useful for limiting the number of active parallel requests a model can process
+    # - must be set per model
+    # - any number greater than 0 will override the internal default value of 10
+    # - any requests that exceeds the limit will receive an HTTP 429 Too Many Requests response
+    # - recommended to be omitted and the default used
+    concurrencyLimit: 0
+
   # Unlisted model example:
   "qwen-unlisted":
-    # unlisted: true or false
+    # unlisted: boolean, true or false
     # - optional, default: false
-    # - unlisted models do not show up in /v1/models or /upstream lists
+    # - unlisted models do not show up in /v1/models api requests
     # - can be requested as normal through all apis
     unlisted: true
     cmd: llama-server --port ${PORT} -m Llama-3.2-1B-Instruct-Q4_K_M.gguf -ngl 0
 
   # Docker example:
-  # container run times like Docker and Podman can also be used with a
+  # container run times like Docker and Podman can be used reliably with a
   # a combination of cmd and cmdStop.
   "docker-llama":
     proxy: "http://127.0.0.1:${PORT}"
@@ -136,24 +161,26 @@ models:
     # cmdStop: command to run to stop the model gracefully
     # - optional, default: ""
     # - useful for stopping commands managed by another system
-    # - on POSIX systems: a SIGTERM is sent for graceful shutdown
-    # - on Windows, taskkill is used
-    # - processes are given 5 seconds to shutdown until they are forcefully killed
     # - the upstream's process id is available in the ${PID} macro
+    #
+    # When empty, llama-swap has this default behaviour:
+    # - on POSIX systems: a SIGTERM signal is sent
+    # - on Windows, calls taskkill to stop the process
+    # - processes have 5 seconds to shutdown until forceful termination is attempted
     cmdStop: docker stop dockertest
 
 # groups: a dictionary of group settings
 # - optional, default: empty dictionary
-# - provide advanced controls over model swapping behaviour.
-# - Using groups some models can be kept loaded indefinitely, while others are swapped out.
-# - model ids must be defined in the Models section
+# - provides advanced controls over model swapping behaviour
+# - using groups some models can be kept loaded indefinitely, while others are swapped out
+# - model IDs must be defined in the Models section
 # - a model can only be a member of one group
 # - group behaviour is controlled via the `swap`, `exclusive` and `persistent` fields
 # - see issue #109 for details
 #
 # NOTE: the example below uses model names that are not defined above for demonstration purposes
 groups:
-  # group1 is same as the default behaviour of llama-swap where only one model is allowed
+  # group1 works the same as the default behaviour of llama-swap where only one model is allowed
   # to run a time across the whole llama-swap instance
   "group1":
     # swap: controls the model swapping behaviour in within the group
@@ -175,10 +202,13 @@ groups:
       - "qwen-unlisted"
 
   # Example:
-  # - in this group all the models can run at the same time
-  # - when a different group loads all running models in this group are unloaded
+  # - in group2 all models can run at the same time
+  # - when a different group is loaded it causes all running models in this group to unload
   "group2":
     swap: false
+
+    # exclusive: false does not unload other groups when a model in group2 is requested
+    # - the models in group2 will be loaded but will not unload any other groups
     exclusive: false
     members:
       - "docker-llama"
@@ -200,4 +230,20 @@ groups:
     members:
       - "forever-modelA"
       - "forever-modelB"
-      - "forever-modelc"
+      - "forever-modelc"
+
+# hooks: a dictionary of event triggers and actions
+# - optional, default: empty dictionary
+# - the only supported hook is on_startup
+hooks:
+  # on_startup: a dictionary of actions to perform on startup
+  # - optional, default: empty dictionary
+  # - the only supported action is preload
+  on_startup:
+        # preload: a list of model ids to load on startup
+        # - optional, default: empty list
+        # - model names must match keys in the models sections
+        # - when preloading multiple models at once, define a group
+        #   otherwise models will be loaded and swapped out
+    preload:
+      - "llama"

docker/config.example.yaml

@@ -1,5 +1,6 @@
 healthCheckTimeout: 300
 logRequests: true
+metricsMaxInMemory: 1000
 
 models:
   "qwen2.5":

event/README.md

@@ -0,0 +1,3 @@
+The code in `event` was originally a part of https://github.com/kelindar/event (v1.5.2)
+
+The original code uses a `time.Ticker` to process the event queue which caused a large increase in CPU usage ([#189](https://github.com/mostlygeek/llama-swap/issues/189)). This code was ported to remove the ticker and instead be more event driven.

event/default.go

@@ -0,0 +1,30 @@
+// Copyright (c) Roman Atachiants and contributore. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for detaile.
+
+package event
+
+import (
+	"context"
+)
+
+// Default initializes a default in-process dispatcher
+var Default = NewDispatcherConfig(25000)
+
+// On subscribes to an event, the type of the event will be automatically
+// inferred from the provided type. Must be constant for this to work. This
+// functions same way as Subscribe() but uses the default dispatcher instead.
+func On[T Event](handler func(T)) context.CancelFunc {
+	return Subscribe(Default, handler)
+}
+
+// OnType subscribes to an event with the specified event type. This functions
+// same way as SubscribeTo() but uses the default dispatcher instead.
+func OnType[T Event](eventType uint32, handler func(T)) context.CancelFunc {
+	return SubscribeTo(Default, eventType, handler)
+}
+
+// Emit writes an event into the dispatcher. This functions same way as
+// Publish() but uses the default dispatcher instead.
+func Emit[T Event](ev T) {
+	Publish(Default, ev)
+}

event/default_test.go

@@ -0,0 +1,54 @@
+// Copyright (c) Roman Atachiants and contributore. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for detaile.
+
+package event
+
+import (
+	"sync"
+	"sync/atomic"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+/*
+cpu: 13th Gen Intel(R) Core(TM) i7-13700K
+BenchmarkSubcribeConcurrent-24    	 1826686	       606.3 ns/op	    1648 B/op	       5 allocs/op
+*/
+func BenchmarkSubscribeConcurrent(b *testing.B) {
+	d := NewDispatcher()
+	b.ReportAllocs()
+	b.ResetTimer()
+
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			unsub := Subscribe(d, func(ev MyEvent1) {})
+			unsub()
+		}
+	})
+}
+
+func TestDefaultPublish(t *testing.T) {
+	var wg sync.WaitGroup
+
+	// Subscribe
+	var count int64
+	defer On(func(ev MyEvent1) {
+		atomic.AddInt64(&count, 1)
+		wg.Done()
+	})()
+
+	defer OnType(TypeEvent1, func(ev MyEvent1) {
+		atomic.AddInt64(&count, 1)
+		wg.Done()
+	})()
+
+	// Publish
+	wg.Add(4)
+	Emit(MyEvent1{})
+	Emit(MyEvent1{})
+
+	// Wait and check
+	wg.Wait()
+	assert.Equal(t, int64(4), count)
+}

event/event.go

@@ -0,0 +1,324 @@
+// Copyright (c) Roman Atachiants and contributors. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for details.
+
+package event
+
+import (
+	"context"
+	"fmt"
+	"reflect"
+	"sort"
+	"strings"
+	"sync"
+	"sync/atomic"
+)
+
+// Event represents an event contract
+type Event interface {
+	Type() uint32
+}
+
+// registry holds an immutable sorted array of event mappings
+type registry struct {
+	keys []uint32 // Event types (sorted)
+	grps []any    // Corresponding subscribers
+}
+
+// ------------------------------------- Dispatcher -------------------------------------
+
+// Dispatcher represents an event dispatcher.
+type Dispatcher struct {
+	subs     atomic.Pointer[registry] // Atomic pointer to immutable array
+	done     chan struct{}            // Cancellation
+	maxQueue int                      // Maximum queue size per consumer
+	mu       sync.Mutex               // Only for writes (subscribe/unsubscribe)
+}
+
+// NewDispatcher creates a new dispatcher of events.
+func NewDispatcher() *Dispatcher {
+	return NewDispatcherConfig(50000)
+}
+
+// NewDispatcherConfig creates a new dispatcher with configurable max queue size
+func NewDispatcherConfig(maxQueue int) *Dispatcher {
+	d := &Dispatcher{
+		done:     make(chan struct{}),
+		maxQueue: maxQueue,
+	}
+
+	d.subs.Store(&registry{
+		keys: make([]uint32, 0, 16),
+		grps: make([]any, 0, 16),
+	})
+	return d
+}
+
+// Close closes the dispatcher
+func (d *Dispatcher) Close() error {
+	close(d.done)
+	return nil
+}
+
+// isClosed returns whether the dispatcher is closed or not
+func (d *Dispatcher) isClosed() bool {
+	select {
+	case <-d.done:
+		return true
+	default:
+		return false
+	}
+}
+
+// findGroup performs a lock-free binary search for the event type
+func (d *Dispatcher) findGroup(eventType uint32) any {
+	reg := d.subs.Load()
+	keys := reg.keys
+
+	// Inlined binary search for better cache locality
+	left, right := 0, len(keys)
+	for left < right {
+		mid := left + (right-left)/2
+		if keys[mid] < eventType {
+			left = mid + 1
+		} else {
+			right = mid
+		}
+	}
+
+	if left < len(keys) && keys[left] == eventType {
+		return reg.grps[left]
+	}
+	return nil
+}
+
+// Subscribe subscribes to an event, the type of the event will be automatically
+// inferred from the provided type. Must be constant for this to work.
+func Subscribe[T Event](broker *Dispatcher, handler func(T)) context.CancelFunc {
+	var event T
+	return SubscribeTo(broker, event.Type(), handler)
+}
+
+// SubscribeTo subscribes to an event with the specified event type.
+func SubscribeTo[T Event](broker *Dispatcher, eventType uint32, handler func(T)) context.CancelFunc {
+	if broker.isClosed() {
+		panic(errClosed)
+	}
+
+	broker.mu.Lock()
+	defer broker.mu.Unlock()
+
+	// Check if group already exists
+	if existing := broker.findGroup(eventType); existing != nil {
+		grp := groupOf[T](eventType, existing)
+		sub := grp.Add(handler)
+		return func() {
+			grp.Del(sub)
+		}
+	}
+
+	// Create new group
+	grp := &group[T]{cond: sync.NewCond(new(sync.Mutex)), maxQueue: broker.maxQueue}
+	sub := grp.Add(handler)
+
+	// Copy-on-write: insert new entry in sorted position
+	old := broker.subs.Load()
+	idx := sort.Search(len(old.keys), func(i int) bool {
+		return old.keys[i] >= eventType
+	})
+
+	// Create new arrays with space for one more element
+	newKeys := make([]uint32, len(old.keys)+1)
+	newGrps := make([]any, len(old.grps)+1)
+
+	// Copy elements before insertion point
+	copy(newKeys[:idx], old.keys[:idx])
+	copy(newGrps[:idx], old.grps[:idx])
+
+	// Insert new element
+	newKeys[idx] = eventType
+	newGrps[idx] = grp
+
+	// Copy elements after insertion point
+	copy(newKeys[idx+1:], old.keys[idx:])
+	copy(newGrps[idx+1:], old.grps[idx:])
+
+	// Atomically store the new registry (mutex ensures no concurrent writers)
+	newReg := &registry{keys: newKeys, grps: newGrps}
+	broker.subs.Store(newReg)
+
+	return func() {
+		grp.Del(sub)
+	}
+}
+
+// Publish writes an event into the dispatcher
+func Publish[T Event](broker *Dispatcher, ev T) {
+	eventType := ev.Type()
+	if sub := broker.findGroup(eventType); sub != nil {
+		group := groupOf[T](eventType, sub)
+		group.Broadcast(ev)
+	}
+}
+
+// Count counts the number of subscribers, this is for testing only.
+func (d *Dispatcher) count(eventType uint32) int {
+	if group := d.findGroup(eventType); group != nil {
+		return group.(interface{ Count() int }).Count()
+	}
+	return 0
+}
+
+// groupOf casts the subscriber group to the specified generic type
+func groupOf[T Event](eventType uint32, subs any) *group[T] {
+	if group, ok := subs.(*group[T]); ok {
+		return group
+	}
+
+	panic(errConflict[T](eventType, subs))
+}
+
+// ------------------------------------- Subscriber -------------------------------------
+
+// consumer represents a consumer with a message queue
+type consumer[T Event] struct {
+	queue []T  // Current work queue
+	stop  bool // Stop signal
+}
+
+// Listen listens to the event queue and processes events
+func (s *consumer[T]) Listen(c *sync.Cond, fn func(T)) {
+	pending := make([]T, 0, 128)
+
+	for {
+		c.L.Lock()
+		for len(s.queue) == 0 {
+			switch {
+			case s.stop:
+				c.L.Unlock()
+				return
+			default:
+				c.Wait()
+			}
+		}
+
+		// Swap buffers and reset the current queue
+		temp := s.queue
+		s.queue = pending[:0]
+		pending = temp
+		c.L.Unlock()
+
+		// Outside of the critical section, process the work
+		for _, event := range pending {
+			fn(event)
+		}
+
+		// Notify potential publishers waiting due to backpressure
+		c.Broadcast()
+	}
+}
+
+// ------------------------------------- Subscriber Group -------------------------------------
+
+// group represents a consumer group
+type group[T Event] struct {
+	cond     *sync.Cond
+	subs     []*consumer[T]
+	maxQueue int // Maximum queue size per consumer
+	maxLen   int // Current maximum queue length across all consumers
+}
+
+// Broadcast sends an event to all consumers
+func (s *group[T]) Broadcast(ev T) {
+	s.cond.L.Lock()
+	defer s.cond.L.Unlock()
+
+	// Calculate current maximum queue length
+	s.maxLen = 0
+	for _, sub := range s.subs {
+		if len(sub.queue) > s.maxLen {
+			s.maxLen = len(sub.queue)
+		}
+	}
+
+	// Backpressure: wait if queues are full
+	for s.maxLen >= s.maxQueue {
+		s.cond.Wait()
+
+		// Recalculate after wakeup
+		s.maxLen = 0
+		for _, sub := range s.subs {
+			if len(sub.queue) > s.maxLen {
+				s.maxLen = len(sub.queue)
+			}
+		}
+	}
+
+	// Add event to all queues and track new maximum
+	newMax := 0
+	for _, sub := range s.subs {
+		sub.queue = append(sub.queue, ev)
+		if len(sub.queue) > newMax {
+			newMax = len(sub.queue)
+		}
+	}
+	s.maxLen = newMax
+	s.cond.Broadcast() // Wake consumers
+}
+
+// Add adds a subscriber to the list
+func (s *group[T]) Add(handler func(T)) *consumer[T] {
+	sub := &consumer[T]{
+		queue: make([]T, 0, 64),
+	}
+
+	// Add the consumer to the list of active consumers
+	s.cond.L.Lock()
+	s.subs = append(s.subs, sub)
+	s.cond.L.Unlock()
+
+	// Start listening
+	go sub.Listen(s.cond, handler)
+	return sub
+}
+
+// Del removes a subscriber from the list
+func (s *group[T]) Del(sub *consumer[T]) {
+	s.cond.L.Lock()
+	defer s.cond.L.Unlock()
+
+	// Search and remove the subscriber
+	sub.stop = true
+	for i, v := range s.subs {
+		if v == sub {
+			copy(s.subs[i:], s.subs[i+1:])
+			s.subs = s.subs[:len(s.subs)-1]
+			break
+		}
+	}
+}
+
+// ------------------------------------- Debugging -------------------------------------
+
+var errClosed = fmt.Errorf("event dispatcher is closed")
+
+// Count returns the number of subscribers in this group
+func (s *group[T]) Count() int {
+	return len(s.subs)
+}
+
+// String returns string representation of the type
+func (s *group[T]) String() string {
+	typ := reflect.TypeOf(s).String()
+	idx := strings.LastIndex(typ, "/")
+	typ = typ[idx+1 : len(typ)-1]
+	return typ
+}
+
+// errConflict returns a conflict message
+func errConflict[T any](eventType uint32, existing any) string {
+	var want T
+	return fmt.Sprintf(
+		"conflicting event type, want=<%T>, registered=<%s>, event=0x%v",
+		want, existing, eventType,
+	)
+}

event/event_test.go

@@ -0,0 +1,324 @@
+// Copyright (c) Roman Atachiants and contributore. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for detaile.
+
+package event
+
+import (
+	"fmt"
+	"sync"
+	"sync/atomic"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestPublish(t *testing.T) {
+	d := NewDispatcher()
+	var wg sync.WaitGroup
+
+	// Subscribe, must be received in order
+	var count int64
+	defer Subscribe(d, func(ev MyEvent1) {
+		assert.Equal(t, int(atomic.AddInt64(&count, 1)), ev.Number)
+		wg.Done()
+	})()
+
+	// Publish
+	wg.Add(3)
+	Publish(d, MyEvent1{Number: 1})
+	Publish(d, MyEvent1{Number: 2})
+	Publish(d, MyEvent1{Number: 3})
+
+	// Wait and check
+	wg.Wait()
+	assert.Equal(t, int64(3), count)
+}
+
+func TestUnsubscribe(t *testing.T) {
+	d := NewDispatcher()
+	assert.Equal(t, 0, d.count(TypeEvent1))
+	unsubscribe := Subscribe(d, func(ev MyEvent1) {
+		// Nothing
+	})
+
+	assert.Equal(t, 1, d.count(TypeEvent1))
+	unsubscribe()
+	assert.Equal(t, 0, d.count(TypeEvent1))
+}
+
+func TestConcurrent(t *testing.T) {
+	const max = 1000000
+	var count int64
+	var wg sync.WaitGroup
+	wg.Add(1)
+
+	d := NewDispatcher()
+	defer Subscribe(d, func(ev MyEvent1) {
+		if current := atomic.AddInt64(&count, 1); current == max {
+			wg.Done()
+		}
+	})()
+
+	// Asynchronously publish
+	go func() {
+		for i := 0; i < max; i++ {
+			Publish(d, MyEvent1{})
+		}
+	}()
+
+	defer Subscribe(d, func(ev MyEvent1) {
+		// Subscriber that does nothing
+	})()
+
+	wg.Wait()
+	assert.Equal(t, max, int(count))
+}
+
+func TestSubscribeDifferentType(t *testing.T) {
+	d := NewDispatcher()
+	assert.Panics(t, func() {
+		SubscribeTo(d, TypeEvent1, func(ev MyEvent1) {})
+		SubscribeTo(d, TypeEvent1, func(ev MyEvent2) {})
+	})
+}
+
+func TestPublishDifferentType(t *testing.T) {
+	d := NewDispatcher()
+	assert.Panics(t, func() {
+		SubscribeTo(d, TypeEvent1, func(ev MyEvent2) {})
+		Publish(d, MyEvent1{})
+	})
+}
+
+func TestCloseDispatcher(t *testing.T) {
+	d := NewDispatcher()
+	defer SubscribeTo(d, TypeEvent1, func(ev MyEvent2) {})()
+
+	assert.NoError(t, d.Close())
+	assert.Panics(t, func() {
+		SubscribeTo(d, TypeEvent1, func(ev MyEvent2) {})
+	})
+}
+
+func TestMatrix(t *testing.T) {
+	const amount = 1000
+	for _, subs := range []int{1, 10, 100} {
+		for _, topics := range []int{1, 10} {
+			expected := subs * topics * amount
+			t.Run(fmt.Sprintf("%dx%d", topics, subs), func(t *testing.T) {
+				var count atomic.Int64
+				var wg sync.WaitGroup
+				wg.Add(expected)
+
+				d := NewDispatcher()
+				for i := 0; i < subs; i++ {
+					for id := 0; id < topics; id++ {
+						defer SubscribeTo(d, uint32(id), func(ev MyEvent3) {
+							count.Add(1)
+							wg.Done()
+						})()
+					}
+				}
+
+				for n := 0; n < amount; n++ {
+					for id := 0; id < topics; id++ {
+						go Publish(d, MyEvent3{ID: id})
+					}
+				}
+
+				wg.Wait()
+				assert.Equal(t, expected, int(count.Load()))
+			})
+		}
+	}
+}
+
+func TestConcurrentSubscriptionRace(t *testing.T) {
+	// This test specifically targets the race condition that occurs when multiple
+	// goroutines try to subscribe to different event types simultaneously.
+	// Without the CAS loop, subscriptions could be lost due to registry corruption.
+
+	const numGoroutines = 100
+	const numEventTypes = 50
+
+	d := NewDispatcher()
+	defer d.Close()
+
+	var wg sync.WaitGroup
+	var receivedCount int64
+	var subscribedTypes sync.Map // Thread-safe map
+
+	wg.Add(numGoroutines)
+
+	// Start multiple goroutines that subscribe to different event types concurrently
+	for i := 0; i < numGoroutines; i++ {
+		go func(goroutineID int) {
+			defer wg.Done()
+
+			// Each goroutine subscribes to a unique event type
+			eventType := uint32(goroutineID%numEventTypes + 1000) // Offset to avoid collision with other tests
+
+			// Subscribe to the event type
+			SubscribeTo(d, eventType, func(ev MyEvent3) {
+				atomic.AddInt64(&receivedCount, 1)
+			})
+
+			// Record that this type was subscribed
+			subscribedTypes.Store(eventType, true)
+		}(i)
+	}
+
+	// Wait for all subscriptions to complete
+	wg.Wait()
+
+	// Count the number of unique event types subscribed
+	expectedTypes := 0
+	subscribedTypes.Range(func(key, value interface{}) bool {
+		expectedTypes++
+		return true
+	})
+
+	// Small delay to ensure all subscriptions are fully processed
+	time.Sleep(10 * time.Millisecond)
+
+	// Publish events to each subscribed type
+	subscribedTypes.Range(func(key, value interface{}) bool {
+		eventType := key.(uint32)
+		Publish(d, MyEvent3{ID: int(eventType)})
+		return true
+	})
+
+	// Wait for all events to be processed
+	time.Sleep(50 * time.Millisecond)
+
+	// Verify that we received at least the expected number of events
+	// (there might be more if multiple goroutines subscribed to the same event type)
+	received := atomic.LoadInt64(&receivedCount)
+	assert.GreaterOrEqual(t, int(received), expectedTypes,
+		"Should have received at least %d events, got %d", expectedTypes, received)
+
+	// Verify that we have the expected number of unique event types
+	assert.Equal(t, numEventTypes, expectedTypes,
+		"Should have exactly %d unique event types", numEventTypes)
+}
+
+func TestConcurrentHandlerRegistration(t *testing.T) {
+	const numGoroutines = 100
+
+	// Test concurrent subscriptions to the same event type
+	t.Run("SameEventType", func(t *testing.T) {
+		d := NewDispatcher()
+		var handlerCount int64
+		var wg sync.WaitGroup
+
+		// Start multiple goroutines subscribing to the same event type (0x1)
+		for i := 0; i < numGoroutines; i++ {
+			wg.Add(1)
+			go func() {
+				defer wg.Done()
+				SubscribeTo(d, uint32(0x1), func(ev MyEvent1) {
+					atomic.AddInt64(&handlerCount, 1)
+				})
+			}()
+		}
+
+		wg.Wait()
+
+		// Verify all handlers were registered by publishing an event
+		atomic.StoreInt64(&handlerCount, 0)
+		Publish(d, MyEvent1{})
+
+		// Small delay to ensure all handlers have executed
+		time.Sleep(10 * time.Millisecond)
+
+		assert.Equal(t, int64(numGoroutines), atomic.LoadInt64(&handlerCount),
+			"Not all handlers were registered due to race condition")
+	})
+
+	// Test concurrent subscriptions to different event types
+	t.Run("DifferentEventTypes", func(t *testing.T) {
+		d := NewDispatcher()
+		var wg sync.WaitGroup
+		receivedEvents := make(map[uint32]*int64)
+
+		// Create multiple event types and subscribe concurrently
+		for i := 0; i < numGoroutines; i++ {
+			eventType := uint32(100 + i)
+			counter := new(int64)
+			receivedEvents[eventType] = counter
+
+			wg.Add(1)
+			go func(et uint32, cnt *int64) {
+				defer wg.Done()
+				SubscribeTo(d, et, func(ev MyEvent3) {
+					atomic.AddInt64(cnt, 1)
+				})
+			}(eventType, counter)
+		}
+
+		wg.Wait()
+
+		// Publish events to all types
+		for eventType := uint32(100); eventType < uint32(100+numGoroutines); eventType++ {
+			Publish(d, MyEvent3{ID: int(eventType)})
+		}
+
+		// Small delay to ensure all handlers have executed
+		time.Sleep(10 * time.Millisecond)
+
+		// Verify all event types received their events
+		for eventType, counter := range receivedEvents {
+			assert.Equal(t, int64(1), atomic.LoadInt64(counter),
+				"Event type %d did not receive its event", eventType)
+		}
+	})
+}
+
+func TestBackpressure(t *testing.T) {
+	d := NewDispatcher()
+	d.maxQueue = 10
+
+	var processedCount int64
+	unsub := SubscribeTo(d, uint32(0x200), func(ev MyEvent3) {
+		atomic.AddInt64(&processedCount, 1)
+	})
+	defer unsub()
+
+	const eventsToPublish = 1000
+	for i := 0; i < eventsToPublish; i++ {
+		Publish(d, MyEvent3{ID: 0x200})
+	}
+
+	time.Sleep(100 * time.Millisecond)
+
+	// Verify all events were eventually processed
+	finalProcessed := atomic.LoadInt64(&processedCount)
+	assert.Equal(t, int64(eventsToPublish), finalProcessed)
+	t.Logf("Events processed: %d/%d", finalProcessed, eventsToPublish)
+}
+
+// ------------------------------------- Test Events -------------------------------------
+
+const (
+	TypeEvent1 = 0x1
+	TypeEvent2 = 0x2
+)
+
+type MyEvent1 struct {
+	Number int
+}
+
+func (t MyEvent1) Type() uint32 { return TypeEvent1 }
+
+type MyEvent2 struct {
+	Text string
+}
+
+func (t MyEvent2) Type() uint32 { return TypeEvent2 }
+
+type MyEvent3 struct {
+	ID int
+}
+
+func (t MyEvent3) Type() uint32 { return uint32(t.ID) }

go.mod

@@ -3,17 +3,16 @@ module github.com/mostlygeek/llama-swap
 go 1.23.0
 
 require (
+	github.com/billziss-gh/golib v0.2.0
 	github.com/fsnotify/fsnotify v1.9.0
 	github.com/gin-gonic/gin v1.10.0
 	github.com/stretchr/testify v1.9.0
 	github.com/tidwall/gjson v1.18.0
 	github.com/tidwall/sjson v1.2.5
 	gopkg.in/yaml.v3 v3.0.1
-	github.com/kelindar/event v1.5.2
 )
 
 require (
-	github.com/billziss-gh/golib v0.2.0 // indirect
 	github.com/bytedance/sonic v1.11.6 // indirect
 	github.com/bytedance/sonic/loader v0.1.1 // indirect
 	github.com/cloudwego/base64x v0.1.4 // indirect

go.sum

@@ -32,12 +32,8 @@ github.com/goccy/go-json v0.10.2/go.mod h1:6MelG93GURQebXPDq3khkgXZkazVtN9CRI+MG
 github.com/google/go-cmp v0.5.5 h1:Khx7svrCpmxxtHBq5j2mp/xVjsi8hQMfNLvJFAlrGgU=
 github.com/google/go-cmp v0.5.5/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
 github.com/google/gofuzz v1.0.0/go.mod h1:dBl0BpW6vV/+mYPU4Po3pmUjxk6FQPldtuIdl/M65Eg=
-github.com/google/shlex v0.0.0-20191202100458-e7afc7fbc510 h1:El6M4kTTCOh6aBiKaUGG7oYTSPP8MxqL4YI3kZKwcP4=
-github.com/google/shlex v0.0.0-20191202100458-e7afc7fbc510/go.mod h1:pupxD2MaaD3pAXIBCelhxNneeOaAeabZDe5s4K6zSpQ=
 github.com/json-iterator/go v1.1.12 h1:PV8peI4a0ysnczrg+LtxykD8LfKY9ML6u2jnxaEnrnM=
 github.com/json-iterator/go v1.1.12/go.mod h1:e30LSqwooZae/UwlEbR2852Gd8hjQvJoHmT4TnhNGBo=
-github.com/kelindar/event v1.5.2 h1:qtgssZqMh/QQMCIxlbx4wU3DoMHOrJXKdiZhphJ4YbY=
-github.com/kelindar/event v1.5.2/go.mod h1:UxWPQjWK8u0o9Z3ponm2mgREimM95hm26/M9z8F488Q=
 github.com/klauspost/cpuid/v2 v2.0.9/go.mod h1:FInQzS24/EEf25PyTYn52gqo7WaD8xa0213Md/qVLRg=
 github.com/klauspost/cpuid/v2 v2.2.7 h1:ZWSB3igEs+d0qvnxR/ZBzXVmxkgt8DdzP6m9pfuVLDM=
 github.com/klauspost/cpuid/v2 v2.2.7/go.mod h1:Lcz8mBdAVJIBVzewtcLocK12l3Y+JytZYpaMropDUws=

llama-swap.go

@@ -14,7 +14,7 @@ import (
 
 	"github.com/fsnotify/fsnotify"
 	"github.com/gin-gonic/gin"
-	"github.com/kelindar/event"
+	"github.com/mostlygeek/llama-swap/event"
 	"github.com/mostlygeek/llama-swap/proxy"
 )
 
@@ -132,6 +132,11 @@ func main() {
 						event.Emit(proxy.ConfigFileChangedEvent{
 							ReloadingState: proxy.ReloadingStateStart,
 						})
+					} else if changeEvent.Name == filepath.Join(configDir, "..data") && changeEvent.Has(fsnotify.Create) {
+						// the change for k8s configmap
+						event.Emit(proxy.ConfigFileChangedEvent{
+							ReloadingState: proxy.ReloadingStateStart,
+						})
 					}
 
 				case err := <-watcher.Errors:

misc/benchmark-chatcompletion/main.go

@@ -0,0 +1,159 @@
+package main
+
+// created for issue: #252 https://github.com/mostlygeek/llama-swap/issues/252
+// this simple benchmark tool sends a lot of small chat completion requests to llama-swap
+// to make sure all the requests are accounted for.
+//
+// requests can be sent in parallel, and the tool will report the results.
+// usage: go run main.go -baseurl http://localhost:8080/v1 -model llama3 -requests 1000 -par 5
+
+import (
+	"bytes"
+	"flag"
+	"fmt"
+	"io"
+	"log"
+	"net/http"
+	"os"
+	"sync"
+	"time"
+)
+
+func main() {
+	// ----- CLI arguments ----------------------------------------------------
+	var (
+		baseurl         string
+		modelName       string
+		totalRequests   int
+		parallelization int
+	)
+
+	flag.StringVar(&baseurl, "baseurl", "http://localhost:8080/v1", "Base URL of the API (e.g., https://api.example.com)")
+	flag.StringVar(&modelName, "model", "", "Model name to use")
+	flag.IntVar(&totalRequests, "requests", 1, "Total number of requests to send")
+	flag.IntVar(&parallelization, "par", 1, "Maximum number of concurrent requests")
+	flag.Parse()
+
+	if baseurl == "" || modelName == "" {
+		fmt.Println("Error: both -baseurl and -model are required.")
+		flag.Usage()
+		os.Exit(1)
+	}
+	if totalRequests <= 0 {
+		fmt.Println("Error: -requests must be greater than 0.")
+		os.Exit(1)
+	}
+	if parallelization <= 0 {
+		fmt.Println("Error: -parallelization must be greater than 0.")
+		os.Exit(1)
+	}
+
+	// ----- HTTP client -------------------------------------------------------
+	client := &http.Client{
+		Timeout: 30 * time.Second,
+	}
+
+	// ----- Tracking response codes -------------------------------------------
+	statusCounts := make(map[int]int) // map[statusCode]count
+	var mu sync.Mutex                 // protects statusCounts
+
+	// ----- Request queue (buffered channel) ----------------------------------
+	requests := make(chan int, 10) // Buffered channel with capacity 10
+
+	// Goroutine to fill the request queue
+	go func() {
+		for i := 0; i < totalRequests; i++ {
+			requests <- i + 1
+		}
+		close(requests)
+	}()
+
+	// ----- Worker pool -------------------------------------------------------
+	var wg sync.WaitGroup
+	for i := 0; i < parallelization; i++ {
+		wg.Add(1)
+		go func(workerID int) {
+			defer wg.Done()
+
+			for reqID := range requests {
+				// Build request payload as a single line JSON string
+				payload := `{"model":"` + modelName + `","max_tokens":100,"stream":false,"messages":[{"role":"user","content":"write a snake game in python"}]}`
+
+				// Send POST request
+				req, err := http.NewRequest(http.MethodPost,
+					fmt.Sprintf("%s/chat/completions", baseurl),
+					bytes.NewReader([]byte(payload)))
+				if err != nil {
+					log.Printf("[worker %d][req %d] request creation error: %v", workerID, reqID, err)
+					mu.Lock()
+					statusCounts[-1]++
+					mu.Unlock()
+					continue
+				}
+				req.Header.Set("Content-Type", "application/json")
+
+				resp, err := client.Do(req)
+				if err != nil {
+					log.Printf("[worker %d][req %d] HTTP request error: %v", workerID, reqID, err)
+					mu.Lock()
+					statusCounts[-1]++
+					mu.Unlock()
+					continue
+				}
+				io.Copy(io.Discard, resp.Body)
+				resp.Body.Close()
+
+				// Record status code
+				mu.Lock()
+				statusCounts[resp.StatusCode]++
+				mu.Unlock()
+			}
+		}(i + 1)
+	}
+
+	// ----- Status ticker (prints every second) -------------------------------
+	done := make(chan struct{})
+	tickerDone := make(chan struct{})
+	go func() {
+		ticker := time.NewTicker(1 * time.Second)
+		startTime := time.Now()
+		for {
+			select {
+			case <-ticker.C:
+				mu.Lock()
+				// Compute how many requests have completed so far
+				completed := 0
+				for _, cnt := range statusCounts {
+					completed += cnt
+				}
+				// Calculate duration and progress
+				duration := time.Since(startTime)
+				progress := completed * 100 / totalRequests
+				fmt.Printf("Duration: %v, Completed: %d%% requests\n", duration, progress)
+				mu.Unlock()
+			case <-done:
+				duration := time.Since(startTime)
+				fmt.Printf("Duration: %v, Completed: %d%% requests\n", duration, 100)
+				close(tickerDone)
+				return
+			}
+		}
+	}()
+
+	// Wait for all workers to finish
+	wg.Wait()
+	close(done)  // stops the status-update goroutine
+	<-tickerDone // give ticker time to finish / print
+
+	// ----- Summary ------------------------------------------------------------
+	fmt.Println("\n\n=== HTTP response code summary ===")
+	mu.Lock()
+	for code, cnt := range statusCounts {
+		if code == -1 {
+			fmt.Printf("Client-side errors (no HTTP response): %d\n", cnt)
+		} else {
+			fmt.Printf("%d : %d\n", code, cnt)
+		}
+	}
+	mu.Unlock()
+}

misc/simple-responder/simple-responder.go

@@ -35,20 +35,90 @@ func main() {
 
 	// Set up the handler function using the provided response message
 	r.POST("/v1/chat/completions", func(c *gin.Context) {
-		c.Header("Content-Type", "application/json")
-
-		// add a wait to simulate a slow query
-		if wait, err := time.ParseDuration(c.Query("wait")); err == nil {
-			time.Sleep(wait)
-		}
-
 		bodyBytes, _ := io.ReadAll(c.Request.Body)
 
-		c.JSON(http.StatusOK, gin.H{
-			"responseMessage":  *responseMessage,
-			"h_content_length": c.Request.Header.Get("Content-Length"),
-			"request_body":     string(bodyBytes),
-		})
+		// Check if streaming is requested
+		// Query is checked instead of JSON body since that event stream conflicts with other tests
+		isStreaming := c.Query("stream") == "true"
+
+		if isStreaming {
+			// Set headers for streaming
+			c.Header("Content-Type", "text/event-stream")
+			c.Header("Cache-Control", "no-cache")
+			c.Header("Connection", "keep-alive")
+			c.Header("Transfer-Encoding", "chunked")
+
+			// add a wait to simulate a slow query
+			if wait, err := time.ParseDuration(c.Query("wait")); err == nil {
+				time.Sleep(wait)
+			}
+
+			// Send 10 "asdf" tokens
+			for i := 0; i < 10; i++ {
+				data := gin.H{
+					"created": time.Now().Unix(),
+					"choices": []gin.H{
+						{
+							"index": 0,
+							"delta": gin.H{
+								"content": "asdf",
+							},
+							"finish_reason": nil,
+						},
+					},
+				}
+				c.SSEvent("message", data)
+				c.Writer.Flush()
+			}
+
+			// Send final data with usage info
+			finalData := gin.H{
+				"usage": gin.H{
+					"completion_tokens": 10,
+					"prompt_tokens":     25,
+					"total_tokens":      35,
+				},
+				// add timings to simulate llama.cpp
+				"timings": gin.H{
+					"prompt_n":             25,
+					"prompt_ms":            13,
+					"predicted_n":          10,
+					"predicted_ms":         17,
+					"predicted_per_second": 10,
+				},
+			}
+			c.SSEvent("message", finalData)
+			c.Writer.Flush()
+
+			// Send [DONE]
+			c.SSEvent("message", "[DONE]")
+			c.Writer.Flush()
+		} else {
+			c.Header("Content-Type", "application/json")
+
+			// add a wait to simulate a slow query
+			if wait, err := time.ParseDuration(c.Query("wait")); err == nil {
+				time.Sleep(wait)
+			}
+
+			c.JSON(http.StatusOK, gin.H{
+				"responseMessage":  *responseMessage,
+				"h_content_length": c.Request.Header.Get("Content-Length"),
+				"request_body":     string(bodyBytes),
+				"usage": gin.H{
+					"completion_tokens": 10,
+					"prompt_tokens":     25,
+					"total_tokens":      35,
+				},
+				"timings": gin.H{
+					"prompt_n":             25,
+					"prompt_ms":            13,
+					"predicted_n":          10,
+					"predicted_ms":         17,
+					"predicted_per_second": 10,
+				},
+			})
+		}
 	})
 
 	// for issue #62 to check model name strips profile slug
@@ -74,10 +144,28 @@ func main() {
 		c.Header("Content-Type", "application/json")
 		c.JSON(http.StatusOK, gin.H{
 			"responseMessage": *responseMessage,
+			"usage": gin.H{
+				"completion_tokens": 10,
+				"prompt_tokens":     25,
+				"total_tokens":      35,
+			},
 		})
 
 	})
 
+	// llama-server compatibility: /completion
+	r.POST("/completion", func(c *gin.Context) {
+		c.Header("Content-Type", "application/json")
+		c.JSON(http.StatusOK, gin.H{
+			"responseMessage": *responseMessage,
+			"usage": gin.H{
+				"completion_tokens": 10,
+				"prompt_tokens":     25,
+				"total_tokens":      35,
+			},
+		})
+	})
+
 	// issue #41
 	r.POST("/v1/audio/transcriptions", func(c *gin.Context) {
 		// Parse the multipart form

proxy/config.go

@@ -138,10 +138,19 @@ func (c *GroupConfig) UnmarshalYAML(unmarshal func(interface{}) error) error {
 	return nil
 }
 
+type HooksConfig struct {
+	OnStartup HookOnStartup `yaml:"on_startup"`
+}
+
+type HookOnStartup struct {
+	Preload []string `yaml:"preload"`
+}
+
 type Config struct {
 	HealthCheckTimeout int                    `yaml:"healthCheckTimeout"`
 	LogRequests        bool                   `yaml:"logRequests"`
 	LogLevel           string                 `yaml:"logLevel"`
+	MetricsMaxInMemory int                    `yaml:"metricsMaxInMemory"`
 	Models             map[string]ModelConfig `yaml:"models"` /* key is model ID */
 	Profiles           map[string][]string    `yaml:"profiles"`
 	Groups             map[string]GroupConfig `yaml:"groups"` /* key is group ID */
@@ -154,6 +163,9 @@ type Config struct {
 
 	// automatic port assignments
 	StartPort int `yaml:"startPort"`
+
+	// hooks, see: #209
+	Hooks HooksConfig `yaml:"hooks"`
 }
 
 func (c *Config) RealModelName(search string) (string, bool) {
@@ -194,6 +206,7 @@ func LoadConfigFromReader(r io.Reader) (Config, error) {
 		HealthCheckTimeout: 120,
 		StartPort:          5800,
 		LogLevel:           "info",
+		MetricsMaxInMemory: 1000,
 	}
 	err = yaml.Unmarshal(data, &config)
 	if err != nil {
@@ -255,6 +268,10 @@ func LoadConfigFromReader(r io.Reader) (Config, error) {
 	for _, modelId := range modelIds {
 		modelConfig := config.Models[modelId]
 
+		// Strip comments from command fields before macro expansion
+		modelConfig.Cmd = StripComments(modelConfig.Cmd)
+		modelConfig.CmdStop = StripComments(modelConfig.CmdStop)
+
 		// go through model config fields: cmd, cmdStop, proxy, checkEndPoint and replace macros with macro values
 		for macroName, macroValue := range config.Macros {
 			macroSlug := fmt.Sprintf("${%s}", macroName)
@@ -324,6 +341,22 @@ func LoadConfigFromReader(r io.Reader) (Config, error) {
 		}
 	}
 
+	// clean up hooks preload
+	if len(config.Hooks.OnStartup.Preload) > 0 {
+		var toPreload []string
+		for _, modelID := range config.Hooks.OnStartup.Preload {
+			modelID = strings.TrimSpace(modelID)
+			if modelID == "" {
+				continue
+			}
+			if real, found := config.RealModelName(modelID); found {
+				toPreload = append(toPreload, real)
+			}
+		}
+
+		config.Hooks.OnStartup.Preload = toPreload
+	}
+
 	return config, nil
 }
 
@@ -406,3 +439,16 @@ func SanitizeCommand(cmdStr string) ([]string, error) {
 
 	return args, nil
 }
+
+func StripComments(cmdStr string) string {
+	var cleanedLines []string
+	for _, line := range strings.Split(cmdStr, "\n") {
+		trimmed := strings.TrimSpace(line)
+		// Skip comment lines
+		if strings.HasPrefix(trimmed, "#") {
+			continue
+		}
+		cleanedLines = append(cleanedLines, line)
+	}
+	return strings.Join(cleanedLines, "\n")
+}

proxy/config_posix_test.go

@@ -100,6 +100,9 @@ func TestConfig_LoadPosix(t *testing.T) {
 	content := `
 macros:
   svr-path: "path/to/server"
+hooks:
+  on_startup:
+    preload: ["model1", "model2"]
 models:
   model1:
     cmd: path/to/cmd --arg1 one
@@ -163,6 +166,11 @@ groups:
 		Macros: map[string]string{
 			"svr-path": "path/to/server",
 		},
+		Hooks: HooksConfig{
+			OnStartup: HookOnStartup{
+				Preload: []string{"model1", "model2"},
+			},
+		},
 		Models: map[string]ModelConfig{
 			"model1": {
 				Cmd:           "path/to/cmd --arg1 one",
@@ -196,6 +204,7 @@ groups:
 			},
 		},
 		HealthCheckTimeout: 15,
+		MetricsMaxInMemory: 1000,
 		Profiles: map[string][]string{
 			"test": {"model1", "model2"},
 		},

proxy/config_test.go

@@ -1,6 +1,7 @@
 package proxy
 
 import (
+	"slices"
 	"strings"
 	"testing"
 
@@ -325,3 +326,117 @@ models:
 		assert.Equal(t, []string{"temperature", "top_k", "top_p"}, sanitized)
 	}
 }
+
+func TestStripComments(t *testing.T) {
+	tests := []struct {
+		name     string
+		input    string
+		expected string
+	}{
+		{
+			name:     "no comments",
+			input:    "echo hello\necho world",
+			expected: "echo hello\necho world",
+		},
+		{
+			name:     "single comment line",
+			input:    "# this is a comment\necho hello",
+			expected: "echo hello",
+		},
+		{
+			name:     "multiple comment lines",
+			input:    "# comment 1\necho hello\n# comment 2\necho world",
+			expected: "echo hello\necho world",
+		},
+		{
+			name:     "comment with spaces",
+			input:    "   # indented comment\necho hello",
+			expected: "echo hello",
+		},
+		{
+			name:     "empty lines preserved",
+			input:    "echo hello\n\necho world",
+			expected: "echo hello\n\necho world",
+		},
+		{
+			name:     "only comments",
+			input:    "# comment 1\n# comment 2",
+			expected: "",
+		},
+		{
+			name:     "empty string",
+			input:    "",
+			expected: "",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := StripComments(tt.input)
+			if result != tt.expected {
+				t.Errorf("StripComments() = %q, expected %q", result, tt.expected)
+			}
+		})
+	}
+}
+
+func TestConfig_MacroInCommentStrippedBeforeExpansion(t *testing.T) {
+	// Test case that reproduces the original bug where a macro in a comment
+	// would get expanded and cause the comment text to be included in the command
+	content := `
+startPort: 9990
+macros:
+  "latest-llama": >
+    /user/llama.cpp/build/bin/llama-server
+    --port ${PORT}
+
+models:
+  "test-model":
+    cmd: |
+      # ${latest-llama} is a macro that is defined above
+      ${latest-llama}
+      --model /path/to/model.gguf
+      -ngl 99
+`
+
+	config, err := LoadConfigFromReader(strings.NewReader(content))
+	assert.NoError(t, err)
+
+	// Get the sanitized command
+	sanitizedCmd, err := SanitizeCommand(config.Models["test-model"].Cmd)
+	assert.NoError(t, err)
+
+	// Join the command for easier inspection
+	cmdStr := strings.Join(sanitizedCmd, " ")
+
+	// Verify that comment text is NOT present in the final command as separate arguments
+	commentWords := []string{"is", "macro", "that", "defined", "above"}
+	for _, word := range commentWords {
+		found := slices.Contains(sanitizedCmd, word)
+		assert.False(t, found, "Comment text '%s' should not be present as a separate argument in final command", word)
+	}
+
+	// Verify that the actual command components ARE present
+	expectedParts := []string{
+		"/user/llama.cpp/build/bin/llama-server",
+		"--port",
+		"9990",
+		"--model",
+		"/path/to/model.gguf",
+		"-ngl",
+		"99",
+	}
+
+	for _, part := range expectedParts {
+		assert.Contains(t, cmdStr, part, "Expected command part '%s' not found in final command", part)
+	}
+
+	// Verify the server path appears exactly once (not duplicated due to macro expansion)
+	serverPath := "/user/llama.cpp/build/bin/llama-server"
+	count := strings.Count(cmdStr, serverPath)
+	assert.Equal(t, 1, count, "Expected exactly 1 occurrence of server path, found %d", count)
+
+	// Verify the expected final command structure
+	expectedCmd := "/user/llama.cpp/build/bin/llama-server --port 9990 --model /path/to/model.gguf -ngl 99"
+	assert.Equal(t, expectedCmd, cmdStr, "Final command does not match expected structure")
+}

proxy/config_windows_test.go

@@ -193,6 +193,7 @@ groups:
 			},
 		},
 		HealthCheckTimeout: 15,
+		MetricsMaxInMemory: 1000,
 		Profiles: map[string][]string{
 			"test": {"model1", "model2"},
 		},

proxy/discardWriter.go

@@ -0,0 +1,27 @@
+package proxy
+
+import "net/http"
+
+// Custom discard writer that implements http.ResponseWriter but just discards everything
+type DiscardWriter struct {
+	header http.Header
+	status int
+}
+
+func (w *DiscardWriter) Header() http.Header {
+	if w.header == nil {
+		w.header = make(http.Header)
+	}
+	return w.header
+}
+
+func (w *DiscardWriter) Write(data []byte) (int, error) {
+	return len(data), nil
+}
+
+func (w *DiscardWriter) WriteHeader(code int) {
+	w.status = code
+}
+
+// Satisfy the http.Flusher interface for streaming responses
+func (w *DiscardWriter) Flush() {}

proxy/events.go

@@ -6,6 +6,8 @@ const ProcessStateChangeEventID = 0x01
 const ChatCompletionStatsEventID = 0x02
 const ConfigFileChangedEventID = 0x03
 const LogDataEventID = 0x04
+const TokenMetricsEventID = 0x05
+const ModelPreloadedEventID = 0x06
 
 type ProcessStateChangeEvent struct {
 	ProcessName string
@@ -47,3 +49,12 @@ type LogDataEvent struct {
 func (e LogDataEvent) Type() uint32 {
 	return LogDataEventID
 }
+
+type ModelPreloadedEvent struct {
+	ModelName string
+	Success   bool
+}
+
+func (e ModelPreloadedEvent) Type() uint32 {
+	return ModelPreloadedEventID
+}

proxy/helpers_test.go

@@ -13,9 +13,10 @@ import (
 )
 
 var (
-	nextTestPort int = 12000
-	portMutex    sync.Mutex
-	testLogger   = NewLogMonitorWriter(os.Stdout)
+	nextTestPort        int = 12000
+	portMutex           sync.Mutex
+	testLogger          = NewLogMonitorWriter(os.Stdout)
+	simpleResponderPath = getSimpleResponderPath()
 )
 
 // Check if the binary exists
@@ -69,13 +70,11 @@ func getTestSimpleResponderConfig(expectedMessage string) ModelConfig {
 }
 
 func getTestSimpleResponderConfigPort(expectedMessage string, port int) ModelConfig {
-	binaryPath := getSimpleResponderPath()
-
 	// Create a YAML string with just the values we want to set
 	yamlStr := fmt.Sprintf(`
 cmd: '%s --port %d --silent --respond %s'
 proxy: "http://127.0.0.1:%d"
-`, binaryPath, port, expectedMessage, port)
+`, simpleResponderPath, port, expectedMessage, port)
 
 	var cfg ModelConfig
 	if err := yaml.Unmarshal([]byte(yamlStr), &cfg); err != nil {

proxy/logMonitor.go

@@ -8,7 +8,7 @@ import (
 	"os"
 	"sync"
 
-	"github.com/kelindar/event"
+	"github.com/mostlygeek/llama-swap/event"
 )
 
 type LogLevel int
@@ -40,7 +40,7 @@ func NewLogMonitor() *LogMonitor {
 
 func NewLogMonitorWriter(stdout io.Writer) *LogMonitor {
 	return &LogMonitor{
-		eventbus: event.NewDispatcher(),
+		eventbus: event.NewDispatcherConfig(1000),
 		buffer:   ring.New(10 * 1024), // keep 10KB of buffered logs
 		stdout:   stdout,
 		level:    LevelInfo,

proxy/metrics_middleware.go

@@ -0,0 +1,179 @@
+package proxy
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"net/http"
+	"strings"
+	"time"
+
+	"github.com/gin-gonic/gin"
+	"github.com/tidwall/gjson"
+)
+
+type MetricsRecorder struct {
+	metricsMonitor *MetricsMonitor
+	realModelName  string
+	//	isStreaming    bool
+	startTime time.Time
+}
+
+// MetricsMiddleware sets up the MetricsResponseWriter for capturing upstream requests
+func MetricsMiddleware(pm *ProxyManager) gin.HandlerFunc {
+	return func(c *gin.Context) {
+		bodyBytes, err := io.ReadAll(c.Request.Body)
+		if err != nil {
+			pm.sendErrorResponse(c, http.StatusBadRequest, "could not ready request body")
+			c.Abort()
+			return
+		}
+		c.Request.Body = io.NopCloser(bytes.NewBuffer(bodyBytes))
+
+		requestedModel := gjson.GetBytes(bodyBytes, "model").String()
+		if requestedModel == "" {
+			pm.sendErrorResponse(c, http.StatusBadRequest, "missing or invalid 'model' key")
+			c.Abort()
+			return
+		}
+
+		realModelName, found := pm.config.RealModelName(requestedModel)
+		if !found {
+			pm.sendErrorResponse(c, http.StatusBadRequest, fmt.Sprintf("could not find real modelID for %s", requestedModel))
+			c.Abort()
+			return
+		}
+
+		writer := &MetricsResponseWriter{
+			ResponseWriter: c.Writer,
+			metricsRecorder: &MetricsRecorder{
+				metricsMonitor: pm.metricsMonitor,
+				realModelName:  realModelName,
+				startTime:      time.Now(),
+			},
+		}
+		c.Writer = writer
+		c.Next()
+
+		// check for streaming response
+		if strings.Contains(c.Writer.Header().Get("Content-Type"), "text/event-stream") {
+			writer.metricsRecorder.processStreamingResponse(writer.body)
+		} else {
+			writer.metricsRecorder.processNonStreamingResponse(writer.body)
+		}
+
+	}
+}
+
+func (rec *MetricsRecorder) parseAndRecordMetrics(jsonData gjson.Result) bool {
+	usage := jsonData.Get("usage")
+	timings := jsonData.Get("timings")
+	if !usage.Exists() && !timings.Exists() {
+		return false
+	}
+
+	// default values
+	outputTokens := 0
+	inputTokens := 0
+
+	// timings data
+	tokensPerSecond := -1.0
+	promptPerSecond := -1.0
+	durationMs := int(time.Since(rec.startTime).Milliseconds())
+
+	if usage.Exists() {
+		outputTokens = int(jsonData.Get("usage.completion_tokens").Int())
+		inputTokens = int(jsonData.Get("usage.prompt_tokens").Int())
+	}
+
+	// use llama-server's timing data for tok/sec and duration as it is more accurate
+	if timings.Exists() {
+		inputTokens = int(jsonData.Get("timings.prompt_n").Int())
+		outputTokens = int(jsonData.Get("timings.predicted_n").Int())
+		promptPerSecond = jsonData.Get("timings.prompt_per_second").Float()
+		tokensPerSecond = jsonData.Get("timings.predicted_per_second").Float()
+		durationMs = int(jsonData.Get("timings.prompt_ms").Float() + jsonData.Get("timings.predicted_ms").Float())
+	}
+
+	rec.metricsMonitor.addMetrics(TokenMetrics{
+		Timestamp:       time.Now(),
+		Model:           rec.realModelName,
+		InputTokens:     inputTokens,
+		OutputTokens:    outputTokens,
+		PromptPerSecond: promptPerSecond,
+		TokensPerSecond: tokensPerSecond,
+		DurationMs:      durationMs,
+	})
+
+	return true
+}
+
+func (rec *MetricsRecorder) processStreamingResponse(body []byte) {
+	// Iterate **backwards** through the lines looking for the data payload with
+	// usage data
+	lines := bytes.Split(body, []byte("\n"))
+
+	for i := len(lines) - 1; i >= 0; i-- {
+		line := bytes.TrimSpace(lines[i])
+		if len(line) == 0 {
+			continue
+		}
+
+		// SSE payload always follows "data:"
+		prefix := []byte("data:")
+		if !bytes.HasPrefix(line, prefix) {
+			continue
+		}
+		data := bytes.TrimSpace(line[len(prefix):])
+
+		if len(data) == 0 {
+			continue
+		}
+
+		if bytes.Equal(data, []byte("[DONE]")) {
+			// [DONE] line itself contains nothing of interest.
+			continue
+		}
+
+		if gjson.ValidBytes(data) {
+			if rec.parseAndRecordMetrics(gjson.ParseBytes(data)) {
+				return // short circuit if a metric was recorded
+			}
+		}
+	}
+}
+
+func (rec *MetricsRecorder) processNonStreamingResponse(body []byte) {
+	if len(body) == 0 {
+		return
+	}
+
+	// Parse JSON to extract usage information
+	if gjson.ValidBytes(body) {
+		rec.parseAndRecordMetrics(gjson.ParseBytes(body))
+	}
+}
+
+// MetricsResponseWriter captures the entire response for non-streaming
+type MetricsResponseWriter struct {
+	gin.ResponseWriter
+	body            []byte
+	metricsRecorder *MetricsRecorder
+}
+
+func (w *MetricsResponseWriter) Write(b []byte) (int, error) {
+	n, err := w.ResponseWriter.Write(b)
+	if err != nil {
+		return n, err
+	}
+	w.body = append(w.body, b...)
+	return n, nil
+}
+
+func (w *MetricsResponseWriter) WriteHeader(statusCode int) {
+	w.ResponseWriter.WriteHeader(statusCode)
+}
+
+func (w *MetricsResponseWriter) Header() http.Header {
+	return w.ResponseWriter.Header()
+}

proxy/metrics_monitor.go

@@ -0,0 +1,83 @@
+package proxy
+
+import (
+	"encoding/json"
+	"sync"
+	"time"
+
+	"github.com/mostlygeek/llama-swap/event"
+)
+
+// TokenMetrics represents parsed token statistics from llama-server logs
+type TokenMetrics struct {
+	ID              int       `json:"id"`
+	Timestamp       time.Time `json:"timestamp"`
+	Model           string    `json:"model"`
+	InputTokens     int       `json:"input_tokens"`
+	OutputTokens    int       `json:"output_tokens"`
+	PromptPerSecond float64   `json:"prompt_per_second"`
+	TokensPerSecond float64   `json:"tokens_per_second"`
+	DurationMs      int       `json:"duration_ms"`
+}
+
+// TokenMetricsEvent represents a token metrics event
+type TokenMetricsEvent struct {
+	Metrics TokenMetrics
+}
+
+func (e TokenMetricsEvent) Type() uint32 {
+	return TokenMetricsEventID // defined in events.go
+}
+
+// MetricsMonitor parses llama-server output for token statistics
+type MetricsMonitor struct {
+	mu         sync.RWMutex
+	metrics    []TokenMetrics
+	maxMetrics int
+	nextID     int
+}
+
+func NewMetricsMonitor(config *Config) *MetricsMonitor {
+	maxMetrics := config.MetricsMaxInMemory
+	if maxMetrics <= 0 {
+		maxMetrics = 1000 // Default fallback
+	}
+
+	mp := &MetricsMonitor{
+		maxMetrics: maxMetrics,
+	}
+
+	return mp
+}
+
+// addMetrics adds a new metric to the collection and publishes an event
+func (mp *MetricsMonitor) addMetrics(metric TokenMetrics) {
+	mp.mu.Lock()
+	defer mp.mu.Unlock()
+
+	metric.ID = mp.nextID
+	mp.nextID++
+	mp.metrics = append(mp.metrics, metric)
+	if len(mp.metrics) > mp.maxMetrics {
+		mp.metrics = mp.metrics[len(mp.metrics)-mp.maxMetrics:]
+	}
+
+	event.Emit(TokenMetricsEvent{Metrics: metric})
+}
+
+// GetMetrics returns a copy of the current metrics
+func (mp *MetricsMonitor) GetMetrics() []TokenMetrics {
+	mp.mu.RLock()
+	defer mp.mu.RUnlock()
+
+	result := make([]TokenMetrics, len(mp.metrics))
+	copy(result, mp.metrics)
+	return result
+}
+
+// GetMetricsJSON returns metrics as JSON
+func (mp *MetricsMonitor) GetMetricsJSON() ([]byte, error) {
+	mp.mu.RLock()
+	defer mp.mu.RUnlock()
+	return json.Marshal(mp.metrics)
+}

proxy/process.go

@@ -5,6 +5,7 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"net"
 	"net/http"
 	"net/url"
 	"os/exec"
@@ -14,7 +15,7 @@ import (
 	"syscall"
 	"time"
 
-	"github.com/kelindar/event"
+	"github.com/mostlygeek/llama-swap/event"
 )
 
 type ProcessState string
@@ -212,11 +213,11 @@ func (p *Process) start() error {
 		if curState, swapErr := p.swapState(StateStarting, StateStopped); swapErr != nil {
 			p.state = StateStopped // force it into a stopped state
 			return fmt.Errorf(
-				"failed to start command and state swap failed. command error: %v, current state: %v, state swap error: %v",
-				err, curState, swapErr,
+				"failed to start command '%s' and state swap failed. command error: %v, current state: %v, state swap error: %v",
+				strings.Join(args, " "), err, curState, swapErr,
 			)
 		}
-		return fmt.Errorf("start() failed: %v", err)
+		return fmt.Errorf("start() failed for command '%s': %v", strings.Join(args, " "), err)
 	}
 
 	// Capture the exit error for later signalling
@@ -363,8 +364,18 @@ func (p *Process) stopCommand() {
 }
 
 func (p *Process) checkHealthEndpoint(healthURL string) error {
+
 	client := &http.Client{
-		Timeout: 500 * time.Millisecond,
+		// wait a short time for a tcp connection to be established
+		Transport: &http.Transport{
+			DialContext: (&net.Dialer{
+				Timeout: 500 * time.Millisecond,
+			}).DialContext,
+		},
+
+		// give a long time to respond to the health check endpoint
+		// after the connection is established. See issue: 276
+		Timeout: 5000 * time.Millisecond,
 	}
 
 	req, err := http.NewRequest("GET", healthURL, nil)

proxy/process_test.go

@@ -107,7 +107,7 @@ func TestProcess_BrokenModelConfig(t *testing.T) {
 	w = httptest.NewRecorder()
 	process.ProxyRequest(w, req)
 	assert.Equal(t, http.StatusBadGateway, w.Code)
-	assert.Contains(t, w.Body.String(), "start() failed: ")
+	assert.Contains(t, w.Body.String(), "start() failed for command 'nonexistent-command':")
 }
 
 func TestProcess_UnloadAfterTTL(t *testing.T) {

proxy/processgroup.go

@@ -60,10 +60,20 @@ func (pg *ProcessGroup) ProxyRequest(modelID string, writer http.ResponseWriter,
 	if pg.swap {
 		pg.Lock()
 		if pg.lastUsedProcess != modelID {
+
+			// is there something already running?
 			if pg.lastUsedProcess != "" {
 				pg.processes[pg.lastUsedProcess].Stop()
 			}
+
+			// wait for the request to the new model to be fully handled
+			// and prevent race conditions see issue #277
+			pg.processes[modelID].ProxyRequest(writer, request)
 			pg.lastUsedProcess = modelID
+
+			// short circuit and exit
+			pg.Unlock()
+			return nil
 		}
 		pg.Unlock()
 	}

proxy/processgroup_test.go

@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"net/http"
 	"net/http/httptest"
+	"sync"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
@@ -44,32 +45,49 @@ func TestProcessGroup_HasMember(t *testing.T) {
 	assert.False(t, pg.HasMember("model3"))
 }
 
-func TestProcessGroup_ProxyRequestSwapIsTrue(t *testing.T) {
+// TestProcessGroup_ProxyRequestSwapIsTrueParallel tests that when swap is true
+// and multiple requests are made in parallel, only one process is running at a time.
+func TestProcessGroup_ProxyRequestSwapIsTrueParallel(t *testing.T) {
+	var processGroupTestConfig = AddDefaultGroupToConfig(Config{
+		HealthCheckTimeout: 15,
+		Models: map[string]ModelConfig{
+			// use the same listening so if a model is already running, it will fail
+			// this is a way to test that swap isolation is working
+			// properly when there are parallel requests made at the
+			// same time.
+			"model1": getTestSimpleResponderConfigPort("model1", 9832),
+			"model2": getTestSimpleResponderConfigPort("model2", 9832),
+			"model3": getTestSimpleResponderConfigPort("model3", 9832),
+			"model4": getTestSimpleResponderConfigPort("model4", 9832),
+			"model5": getTestSimpleResponderConfigPort("model5", 9832),
+		},
+		Groups: map[string]GroupConfig{
+			"G1": {
+				Swap:    true,
+				Members: []string{"model1", "model2", "model3", "model4", "model5"},
+			},
+		},
+	})
+
 	pg := NewProcessGroup("G1", processGroupTestConfig, testLogger, testLogger)
 	defer pg.StopProcesses(StopWaitForInflightRequest)
 
-	tests := []string{"model1", "model2"}
+	tests := []string{"model1", "model2", "model3", "model4", "model5"}
 
+	var wg sync.WaitGroup
+
+	wg.Add(len(tests))
 	for _, modelName := range tests {
-		t.Run(modelName, func(t *testing.T) {
-			reqBody := `{"x", "y"}`
-			req := httptest.NewRequest("POST", "/v1/chat/completions", bytes.NewBufferString(reqBody))
+		go func(modelName string) {
+			defer wg.Done()
+			req := httptest.NewRequest("POST", "/v1/chat/completions", nil)
 			w := httptest.NewRecorder()
-
 			assert.NoError(t, pg.ProxyRequest(modelName, w, req))
 			assert.Equal(t, http.StatusOK, w.Code)
 			assert.Contains(t, w.Body.String(), modelName)
-
-			// make sure only one process is in the running state
-			count := 0
-			for _, process := range pg.processes {
-				if process.CurrentState() == StateReady {
-					count++
-				}
-			}
-			assert.Equal(t, 1, count)
-		})
+		}(modelName)
 	}
+	wg.Wait()
 }
 
 func TestProcessGroup_ProxyRequestSwapIsFalse(t *testing.T) {

proxy/proxymanager.go

@@ -8,12 +8,14 @@ import (
 	"mime/multipart"
 	"net/http"
 	"os"
+	"sort"
 	"strconv"
 	"strings"
 	"sync"
 	"time"
 
 	"github.com/gin-gonic/gin"
+	"github.com/mostlygeek/llama-swap/event"
 	"github.com/tidwall/gjson"
 	"github.com/tidwall/sjson"
 )
@@ -33,6 +35,8 @@ type ProxyManager struct {
 	upstreamLogger *LogMonitor
 	muxLogger      *LogMonitor
 
+	metricsMonitor *MetricsMonitor
+
 	processGroups map[string]*ProcessGroup
 
 	// shutdown signaling
@@ -78,6 +82,8 @@ func New(config Config) *ProxyManager {
 		muxLogger:      stdoutLogger,
 		upstreamLogger: upstreamLogger,
 
+		metricsMonitor: NewMetricsMonitor(&config),
+
 		processGroups: make(map[string]*ProcessGroup),
 
 		shutdownCtx:    shutdownCtx,
@@ -91,6 +97,35 @@ func New(config Config) *ProxyManager {
 	}
 
 	pm.setupGinEngine()
+
+	// run any startup hooks
+	if len(config.Hooks.OnStartup.Preload) > 0 {
+		// do it in the background, don't block startup -- not sure if good idea yet
+		go func() {
+			discardWriter := &DiscardWriter{}
+			for _, realModelName := range config.Hooks.OnStartup.Preload {
+				proxyLogger.Infof("Preloading model: %s", realModelName)
+				processGroup, _, err := pm.swapProcessGroup(realModelName)
+
+				if err != nil {
+					event.Emit(ModelPreloadedEvent{
+						ModelName: realModelName,
+						Success:   false,
+					})
+					proxyLogger.Errorf("Failed to preload model %s: %v", realModelName, err)
+					continue
+				} else {
+					req, _ := http.NewRequest("GET", "/", nil)
+					processGroup.ProxyRequest(realModelName, discardWriter, req)
+					event.Emit(ModelPreloadedEvent{
+						ModelName: realModelName,
+						Success:   true,
+					})
+				}
+			}
+		}()
+	}
+
 	return pm
 }
 
@@ -149,14 +184,27 @@ func (pm *ProxyManager) setupGinEngine() {
 		c.Next()
 	})
 
-	// Set up routes using the Gin engine
-	pm.ginEngine.POST("/v1/chat/completions", pm.proxyOAIHandler)
-	// Support legacy /v1/completions api, see issue #12
-	pm.ginEngine.POST("/v1/completions", pm.proxyOAIHandler)
+	mm := MetricsMiddleware(pm)
 
-	// Support embeddings
-	pm.ginEngine.POST("/v1/embeddings", pm.proxyOAIHandler)
-	pm.ginEngine.POST("/v1/rerank", pm.proxyOAIHandler)
+	// Set up routes using the Gin engine
+	pm.ginEngine.POST("/v1/chat/completions", mm, pm.proxyOAIHandler)
+	// Support legacy /v1/completions api, see issue #12
+	pm.ginEngine.POST("/v1/completions", mm, pm.proxyOAIHandler)
+
+	// Support embeddings and reranking
+	pm.ginEngine.POST("/v1/embeddings", mm, pm.proxyOAIHandler)
+
+	// llama-server's /reranking endpoint + aliases
+	pm.ginEngine.POST("/reranking", mm, pm.proxyOAIHandler)
+	pm.ginEngine.POST("/rerank", mm, pm.proxyOAIHandler)
+	pm.ginEngine.POST("/v1/rerank", mm, pm.proxyOAIHandler)
+	pm.ginEngine.POST("/v1/reranking", mm, pm.proxyOAIHandler)
+
+	// llama-server's /infill endpoint for code infilling
+	pm.ginEngine.POST("/infill", mm, pm.proxyOAIHandler)
+
+	// llama-server's /completion endpoint
+	pm.ginEngine.POST("/completion", mm, pm.proxyOAIHandler)
 
 	// Support audio/speech endpoint
 	pm.ginEngine.POST("/v1/audio/speech", pm.proxyOAIHandler)
@@ -183,6 +231,9 @@ func (pm *ProxyManager) setupGinEngine() {
 
 	pm.ginEngine.GET("/unload", pm.unloadAllModelsHandler)
 	pm.ginEngine.GET("/running", pm.listRunningProcessesHandler)
+	pm.ginEngine.GET("/health", func(c *gin.Context) {
+		c.String(http.StatusOK, "OK")
+	})
 
 	pm.ginEngine.GET("/favicon.ico", func(c *gin.Context) {
 		if data, err := reactStaticFS.ReadFile("ui_dist/favicon.ico"); err == nil {
@@ -322,6 +373,13 @@ func (pm *ProxyManager) listModelsHandler(c *gin.Context) {
 		data = append(data, record)
 	}
 
+	// Sort by the "id" key
+	sort.Slice(data, func(i, j int) bool {
+		si, _ := data[i]["id"].(string)
+		sj, _ := data[j]["id"].(string)
+		return si < sj
+	})
+
 	// Set CORS headers if origin exists
 	if origin := c.GetHeader("Origin"); origin != "" {
 		c.Header("Access-Control-Allow-Origin", origin)
@@ -342,7 +400,7 @@ func (pm *ProxyManager) proxyToUpstream(c *gin.Context) {
 		return
 	}
 
-	processGroup, _, err := pm.swapProcessGroup(requestedModel)
+	processGroup, realModelName, err := pm.swapProcessGroup(requestedModel)
 	if err != nil {
 		pm.sendErrorResponse(c, http.StatusInternalServerError, fmt.Sprintf("error swapping process group: %s", err.Error()))
 		return
@@ -350,7 +408,7 @@ func (pm *ProxyManager) proxyToUpstream(c *gin.Context) {
 
 	// rewrite the path
 	c.Request.URL.Path = c.Param("upstreamPath")
-	processGroup.ProxyRequest(requestedModel, c.Writer, c.Request)
+	processGroup.ProxyRequest(realModelName, c.Writer, c.Request)
 }
 
 func (pm *ProxyManager) proxyOAIHandler(c *gin.Context) {
@@ -366,7 +424,13 @@ func (pm *ProxyManager) proxyOAIHandler(c *gin.Context) {
 		return
 	}
 
-	processGroup, realModelName, err := pm.swapProcessGroup(requestedModel)
+	realModelName, found := pm.config.RealModelName(requestedModel)
+	if !found {
+		pm.sendErrorResponse(c, http.StatusBadRequest, fmt.Sprintf("could not find real modelID for %s", requestedModel))
+		return
+	}
+
+	processGroup, _, err := pm.swapProcessGroup(realModelName)
 	if err != nil {
 		pm.sendErrorResponse(c, http.StatusInternalServerError, fmt.Sprintf("error swapping process group: %s", err.Error()))
 		return

proxy/proxymanager_api.go

@@ -7,7 +7,7 @@ import (
 	"sort"
 
 	"github.com/gin-gonic/gin"
-	"github.com/kelindar/event"
+	"github.com/mostlygeek/llama-swap/event"
 )
 
 type Model struct {
@@ -24,6 +24,7 @@ func addApiHandlers(pm *ProxyManager) {
 	{
 		apiGroup.POST("/models/unload", pm.apiUnloadAllModels)
 		apiGroup.GET("/events", pm.apiSendEvents)
+		apiGroup.GET("/metrics", pm.apiGetMetrics)
 	}
 }
 
@@ -85,6 +86,7 @@ type messageType string
 const (
 	msgTypeModelStatus messageType = "modelStatus"
 	msgTypeLogData     messageType = "logData"
+	msgTypeMetrics     messageType = "metrics"
 )
 
 type messageEnvelope struct {
@@ -130,6 +132,18 @@ func (pm *ProxyManager) apiSendEvents(c *gin.Context) {
 		}
 	}
 
+	sendMetrics := func(metrics []TokenMetrics) {
+		jsonData, err := json.Marshal(metrics)
+		if err == nil {
+			select {
+			case sendBuffer <- messageEnvelope{Type: msgTypeMetrics, Data: string(jsonData)}:
+			case <-ctx.Done():
+				return
+			default:
+			}
+		}
+	}
+
 	/**
 	 * Send updated models list
 	 */
@@ -150,10 +164,18 @@ func (pm *ProxyManager) apiSendEvents(c *gin.Context) {
 		sendLogData("upstream", data)
 	})()
 
+	/**
+	 * Send Metrics data
+	 */
+	defer event.On(func(e TokenMetricsEvent) {
+		sendMetrics([]TokenMetrics{e.Metrics})
+	})()
+
 	// send initial batch of data
 	sendLogData("proxy", pm.proxyLogger.GetHistory())
 	sendLogData("upstream", pm.upstreamLogger.GetHistory())
 	sendModels()
+	sendMetrics(pm.metricsMonitor.GetMetrics())
 
 	for {
 		select {
@@ -169,3 +191,12 @@ func (pm *ProxyManager) apiSendEvents(c *gin.Context) {
 		}
 	}
 }
+
+func (pm *ProxyManager) apiGetMetrics(c *gin.Context) {
+	jsonData, err := pm.metricsMonitor.GetMetricsJSON()
+	if err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to get metrics"})
+		return
+	}
+	c.Data(http.StatusOK, "application/json", jsonData)
+}

proxy/proxymanager_test.go

@@ -9,10 +9,12 @@ import (
 	"net/http"
 	"net/http/httptest"
 	"strconv"
+	"strings"
 	"sync"
 	"testing"
 	"time"
 
+	"github.com/mostlygeek/llama-swap/event"
 	"github.com/stretchr/testify/assert"
 	"github.com/tidwall/gjson"
 )
@@ -40,7 +42,6 @@ func TestProxyManager_SwapProcessCorrectly(t *testing.T) {
 		assert.Contains(t, w.Body.String(), modelName)
 	}
 }
-
 func TestProxyManager_SwapMultiProcess(t *testing.T) {
 	config := AddDefaultGroupToConfig(Config{
 		HealthCheckTimeout: 15,
@@ -165,9 +166,11 @@ func TestProxyManager_SwapMultiProcessParallelRequests(t *testing.T) {
 			}
 
 			mu.Lock()
-			var response map[string]string
+			var response map[string]interface{}
 			assert.NoError(t, json.Unmarshal(w.Body.Bytes(), &response))
-			results[key] = response["responseMessage"]
+			result, ok := response["responseMessage"].(string)
+			assert.Equal(t, ok, true)
+			results[key] = result
 			mu.Unlock()
 		}(key)
 
@@ -277,6 +280,51 @@ func TestProxyManager_ListModelsHandler(t *testing.T) {
 	assert.Empty(t, expectedModels, "not all expected models were returned")
 }
 
+func TestProxyManager_ListModelsHandler_SortedByID(t *testing.T) {
+	// Intentionally add models in non-sorted order and with an unlisted model
+	config := Config{
+		HealthCheckTimeout: 15,
+		Models: map[string]ModelConfig{
+			"zeta":  getTestSimpleResponderConfig("zeta"),
+			"alpha": getTestSimpleResponderConfig("alpha"),
+			"beta":  getTestSimpleResponderConfig("beta"),
+			"hidden": func() ModelConfig {
+				mc := getTestSimpleResponderConfig("hidden")
+				mc.Unlisted = true
+				return mc
+			}(),
+		},
+		LogLevel: "error",
+	}
+
+	proxy := New(config)
+
+	// Request models list
+	req := httptest.NewRequest("GET", "/v1/models", nil)
+	w := httptest.NewRecorder()
+	proxy.ServeHTTP(w, req)
+
+	assert.Equal(t, http.StatusOK, w.Code)
+
+	var response struct {
+		Data []map[string]interface{} `json:"data"`
+	}
+	if err := json.Unmarshal(w.Body.Bytes(), &response); err != nil {
+		t.Fatalf("Failed to parse JSON response: %v", err)
+	}
+
+	// We expect only the listed models in sorted order by id
+	expectedOrder := []string{"alpha", "beta", "zeta"}
+	if assert.Len(t, response.Data, len(expectedOrder), "unexpected number of listed models") {
+		got := make([]string, 0, len(response.Data))
+		for _, m := range response.Data {
+			id, _ := m["id"].(string)
+			got = append(got, id)
+		}
+		assert.Equal(t, expectedOrder, got, "models should be sorted by id ascending")
+	}
+}
+
 func TestProxyManager_Shutdown(t *testing.T) {
 	// make broken model configurations
 	model1Config := getTestSimpleResponderConfigPort("model1", 9991)
@@ -609,21 +657,34 @@ func TestProxyManager_CORSOptionsHandler(t *testing.T) {
 }
 
 func TestProxyManager_Upstream(t *testing.T) {
-	config := AddDefaultGroupToConfig(Config{
-		HealthCheckTimeout: 15,
-		Models: map[string]ModelConfig{
-			"model1": getTestSimpleResponderConfig("model1"),
-		},
-		LogLevel: "error",
-	})
+	configStr := fmt.Sprintf(`
+logLevel: error
+models:
+  model1:
+    cmd: %s -port ${PORT} -silent -respond model1
+    aliases: [model-alias]
+`, getSimpleResponderPath())
+
+	config, err := LoadConfigFromReader(strings.NewReader(configStr))
+	assert.NoError(t, err)
 
 	proxy := New(config)
 	defer proxy.StopProcesses(StopWaitForInflightRequest)
-	req := httptest.NewRequest("GET", "/upstream/model1/test", nil)
-	rec := httptest.NewRecorder()
-	proxy.ServeHTTP(rec, req)
-	assert.Equal(t, http.StatusOK, rec.Code)
-	assert.Equal(t, "model1", rec.Body.String())
+	t.Run("main model name", func(t *testing.T) {
+		req := httptest.NewRequest("GET", "/upstream/model1/test", nil)
+		rec := httptest.NewRecorder()
+		proxy.ServeHTTP(rec, req)
+		assert.Equal(t, http.StatusOK, rec.Code)
+		assert.Equal(t, "model1", rec.Body.String())
+	})
+
+	t.Run("model alias", func(t *testing.T) {
+		req := httptest.NewRequest("GET", "/upstream/model-alias/test", nil)
+		rec := httptest.NewRecorder()
+		proxy.ServeHTTP(rec, req)
+		assert.Equal(t, http.StatusOK, rec.Code)
+		assert.Equal(t, "model1", rec.Body.String())
+	})
 }
 
 func TestProxyManager_ChatContentLength(t *testing.T) {
@@ -644,7 +705,7 @@ func TestProxyManager_ChatContentLength(t *testing.T) {
 
 	proxy.ServeHTTP(w, req)
 	assert.Equal(t, http.StatusOK, w.Code)
-	var response map[string]string
+	var response map[string]interface{}
 	assert.NoError(t, json.Unmarshal(w.Body.Bytes(), &response))
 	assert.Equal(t, "81", response["h_content_length"])
 	assert.Equal(t, "model1", response["responseMessage"])
@@ -672,7 +733,7 @@ func TestProxyManager_FiltersStripParams(t *testing.T) {
 
 	proxy.ServeHTTP(w, req)
 	assert.Equal(t, http.StatusOK, w.Code)
-	var response map[string]string
+	var response map[string]interface{}
 	assert.NoError(t, json.Unmarshal(w.Body.Bytes(), &response))
 
 	// `temperature` and `stream` are gone but model remains
@@ -683,3 +744,172 @@ func TestProxyManager_FiltersStripParams(t *testing.T) {
 	// assert.Equal(t, "abc", response["y_param"])
 	// t.Logf("%v", response)
 }
+
+func TestProxyManager_MiddlewareWritesMetrics_NonStreaming(t *testing.T) {
+	config := AddDefaultGroupToConfig(Config{
+		HealthCheckTimeout: 15,
+		Models: map[string]ModelConfig{
+			"model1": getTestSimpleResponderConfig("model1"),
+		},
+		LogLevel: "error",
+	})
+
+	proxy := New(config)
+	defer proxy.StopProcesses(StopWaitForInflightRequest)
+
+	// Make a non-streaming request
+	reqBody := `{"model":"model1", "stream": false}`
+	req := httptest.NewRequest("POST", "/v1/chat/completions", bytes.NewBufferString(reqBody))
+	w := httptest.NewRecorder()
+
+	proxy.ServeHTTP(w, req)
+	assert.Equal(t, http.StatusOK, w.Code)
+
+	// Check that metrics were recorded
+	metrics := proxy.metricsMonitor.GetMetrics()
+	if !assert.NotEmpty(t, metrics, "metrics should be recorded for non-streaming request") {
+		return
+	}
+
+	// Verify the last metric has the correct model
+	lastMetric := metrics[len(metrics)-1]
+	assert.Equal(t, "model1", lastMetric.Model)
+	assert.Equal(t, 25, lastMetric.InputTokens, "input tokens should be 25")
+	assert.Equal(t, 10, lastMetric.OutputTokens, "output tokens should be 10")
+	assert.Greater(t, lastMetric.TokensPerSecond, 0.0, "tokens per second should be greater than 0")
+	assert.Greater(t, lastMetric.DurationMs, 0, "duration should be greater than 0")
+}
+
+func TestProxyManager_MiddlewareWritesMetrics_Streaming(t *testing.T) {
+	config := AddDefaultGroupToConfig(Config{
+		HealthCheckTimeout: 15,
+		Models: map[string]ModelConfig{
+			"model1": getTestSimpleResponderConfig("model1"),
+		},
+		LogLevel: "error",
+	})
+
+	proxy := New(config)
+	defer proxy.StopProcesses(StopWaitForInflightRequest)
+
+	// Make a streaming request
+	reqBody := `{"model":"model1", "stream": true}`
+	req := httptest.NewRequest("POST", "/v1/chat/completions?stream=true", bytes.NewBufferString(reqBody))
+	w := httptest.NewRecorder()
+
+	proxy.ServeHTTP(w, req)
+	assert.Equal(t, http.StatusOK, w.Code)
+
+	// Check that metrics were recorded
+	metrics := proxy.metricsMonitor.GetMetrics()
+	if !assert.NotEmpty(t, metrics, "metrics should be recorded for streaming request") {
+		return
+	}
+
+	// Verify the last metric has the correct model
+	lastMetric := metrics[len(metrics)-1]
+	assert.Equal(t, "model1", lastMetric.Model)
+	assert.Equal(t, 25, lastMetric.InputTokens, "input tokens should be 25")
+	assert.Equal(t, 10, lastMetric.OutputTokens, "output tokens should be 10")
+	assert.Greater(t, lastMetric.TokensPerSecond, 0.0, "tokens per second should be greater than 0")
+	assert.Greater(t, lastMetric.DurationMs, 0, "duration should be greater than 0")
+}
+
+func TestProxyManager_HealthEndpoint(t *testing.T) {
+	config := AddDefaultGroupToConfig(Config{
+		HealthCheckTimeout: 15,
+		Models: map[string]ModelConfig{
+			"model1": getTestSimpleResponderConfig("model1"),
+		},
+		LogLevel: "error",
+	})
+
+	proxy := New(config)
+	defer proxy.StopProcesses(StopWaitForInflightRequest)
+	req := httptest.NewRequest("GET", "/health", nil)
+	rec := httptest.NewRecorder()
+	proxy.ServeHTTP(rec, req)
+	assert.Equal(t, http.StatusOK, rec.Code)
+	assert.Equal(t, "OK", rec.Body.String())
+}
+
+// Ensure the custom llama-server /completion endpoint proxies correctly
+func TestProxyManager_CompletionEndpoint(t *testing.T) {
+	config := AddDefaultGroupToConfig(Config{
+		HealthCheckTimeout: 15,
+		Models: map[string]ModelConfig{
+			"model1": getTestSimpleResponderConfig("model1"),
+		},
+		LogLevel: "error",
+	})
+
+	proxy := New(config)
+	defer proxy.StopProcesses(StopWaitForInflightRequest)
+
+	reqBody := `{"model":"model1"}`
+	req := httptest.NewRequest("POST", "/completion", bytes.NewBufferString(reqBody))
+	w := httptest.NewRecorder()
+
+	proxy.ServeHTTP(w, req)
+	assert.Equal(t, http.StatusOK, w.Code)
+	assert.Contains(t, w.Body.String(), "model1")
+}
+
+func TestProxyManager_StartupHooks(t *testing.T) {
+
+	// using real YAML as the configuration has gotten more complex
+	// is the right approach as LoadConfigFromReader() does a lot more
+	// than parse YAML now. Eventually migrate all tests to use this approach
+	configStr := strings.Replace(`
+logLevel: error
+hooks:
+  on_startup:
+    preload:
+      - model1
+      - model2
+groups:
+  preloadTestGroup:
+    swap: false
+    members:
+       - model1
+       - model2
+models:
+  model1:
+    cmd: ${simpleresponderpath} --port ${PORT} --silent --respond model1
+  model2:
+      cmd: ${simpleresponderpath} --port ${PORT} --silent --respond model2
+`, "${simpleresponderpath}", simpleResponderPath, -1)
+
+	// Create a test model configuration
+	config, err := LoadConfigFromReader(strings.NewReader(configStr))
+	if !assert.NoError(t, err, "Invalid configuration") {
+		return
+	}
+
+	preloadChan := make(chan ModelPreloadedEvent, 2) // buffer for 2 expected events
+
+	unsub := event.On(func(e ModelPreloadedEvent) {
+		preloadChan <- e
+	})
+
+	defer unsub()
+
+	// Create the proxy which should trigger preloading
+	proxy := New(config)
+	defer proxy.StopProcesses(StopWaitForInflightRequest)
+
+	for i := 0; i < 2; i++ {
+		select {
+		case <-preloadChan:
+		case <-time.After(5 * time.Second):
+			t.Fatal("timed out waiting for models to preload")
+		}
+	}
+	// make sure they are both loaded
+	_, foundGroup := proxy.processGroups["preloadTestGroup"]
+	if !assert.True(t, foundGroup, "preloadTestGroup should exist") {
+		return
+	}
+	assert.Equal(t, StateReady, proxy.processGroups["preloadTestGroup"].processes["model1"].CurrentState())
+	assert.Equal(t, StateReady, proxy.processGroups["preloadTestGroup"].processes["model2"].CurrentState())
+}

ui/package-lock.json

@@ -12,6 +12,8 @@
         "@tanstack/react-query": "^5.80.6",
         "react": "^19.1.0",
         "react-dom": "^19.1.0",
+        "react-icons": "^5.5.0",
+        "react-resizable-panels": "^3.0.4",
         "react-router-dom": "^7.6.2",
         "tailwindcss": "^4.1.8"
       },
@@ -3460,6 +3462,15 @@
         "react": "^19.1.0"
       }
     },
+    "node_modules/react-icons": {
+      "version": "5.5.0",
+      "resolved": "https://registry.npmjs.org/react-icons/-/react-icons-5.5.0.tgz",
+      "integrity": "sha512-MEFcXdkP3dLo8uumGI5xN3lDFNsRtrjbOEKDLD7yv76v4wpnEq2Lt2qeHaQOr34I/wPN3s3+N08WkQ+CW37Xiw==",
+      "license": "MIT",
+      "peerDependencies": {
+        "react": "*"
+      }
+    },
     "node_modules/react-refresh": {
       "version": "0.17.0",
       "resolved": "https://registry.npmjs.org/react-refresh/-/react-refresh-0.17.0.tgz",
@@ -3470,6 +3481,16 @@
         "node": ">=0.10.0"
       }
     },
+    "node_modules/react-resizable-panels": {
+      "version": "3.0.4",
+      "resolved": "https://registry.npmjs.org/react-resizable-panels/-/react-resizable-panels-3.0.4.tgz",
+      "integrity": "sha512-8Y4KNgV94XhUvI2LeByyPIjoUJb71M/0hyhtzkHaqpVHs+ZQs8b627HmzyhmVYi3C9YP6R+XD1KmG7hHjEZXFQ==",
+      "license": "MIT",
+      "peerDependencies": {
+        "react": "^16.14.0 || ^17.0.0 || ^18.0.0 || ^19.0.0 || ^19.0.0-rc",
+        "react-dom": "^16.14.0 || ^17.0.0 || ^18.0.0 || ^19.0.0 || ^19.0.0-rc"
+      }
+    },
     "node_modules/react-router": {
       "version": "7.6.2",
       "resolved": "https://registry.npmjs.org/react-router/-/react-router-7.6.2.tgz",

ui/package.json

@@ -14,6 +14,8 @@
     "@tanstack/react-query": "^5.80.6",
     "react": "^19.1.0",
     "react-dom": "^19.1.0",
+    "react-icons": "^5.5.0",
+    "react-resizable-panels": "^3.0.4",
     "react-router-dom": "^7.6.2",
     "tailwindcss": "^4.1.8"
   },
@@ -30,4 +32,4 @@
     "typescript-eslint": "^8.30.1",
     "vite": "^6.3.5"
   }
-}
+}

ui/src/App.tsx

@@ -1,42 +1,78 @@
+import { useEffect, useCallback } from "react";
 import { BrowserRouter as Router, Routes, Route, Navigate, NavLink } from "react-router-dom";
 import { useTheme } from "./contexts/ThemeProvider";
-import { APIProvider } from "./contexts/APIProvider";
+import { useAPI } from "./contexts/APIProvider";
 import LogViewerPage from "./pages/LogViewer";
 import ModelPage from "./pages/Models";
+import ActivityPage from "./pages/Activity";
+import ConnectionStatusIcon from "./components/ConnectionStatus";
+import { RiSunFill, RiMoonFill } from "react-icons/ri";
 
 function App() {
-  const theme = useTheme();
+  const { isNarrow, toggleTheme, isDarkMode, appTitle, setAppTitle, setConnectionState } = useTheme();
+  const handleTitleChange = useCallback(
+    (newTitle: string) => {
+      setAppTitle(newTitle.replace(/\n/g, "").trim().substring(0, 64) || "llama-swap");
+    },
+    [setAppTitle]
+  );
+
+  const { connectionStatus } = useAPI();
+
+  // Synchronize the window.title connections state with the actual connection state
+  useEffect(() => {
+    setConnectionState(connectionStatus);
+  }, [connectionStatus]);
+
   return (
     <Router basename="/ui/">
-      <APIProvider>
-        <div>
-          <nav className="bg-surface border-b border-border p-2 h-[75px]">
-            <div className="flex items-center justify-between mx-auto px-4 h-full">
-              <h1 className="flex items-center p-0">llama-swap</h1>
-              <div className="flex items-center space-x-4">
-                <NavLink to="/" className={({ isActive }) => (isActive ? "navlink active" : "navlink")}>
-                  Logs
-                </NavLink>
-
-                <NavLink to="/models" className={({ isActive }) => (isActive ? "navlink active" : "navlink")}>
-                  Models
-                </NavLink>
-                <button className="btn btn--sm" onClick={theme.toggleTheme}>
-                  {theme.isDarkMode ? "🌙" : "☀️"}
-                </button>
-              </div>
+      <div className="flex flex-col h-screen">
+        <nav className="bg-surface border-b border-border p-2 h-[75px]">
+          <div className="flex items-center justify-between mx-auto px-4 h-full">
+            {!isNarrow && (
+              <h1
+                contentEditable
+                suppressContentEditableWarning
+                className="flex items-center p-0 outline-none hover:bg-gray-100 dark:hover:bg-gray-700 rounded px-1"
+                onBlur={(e) => handleTitleChange(e.currentTarget.textContent || "(set title)")}
+                onKeyDown={(e) => {
+                  if (e.key === "Enter") {
+                    e.preventDefault();
+                    handleTitleChange(e.currentTarget.textContent || "(set title)");
+                    e.currentTarget.blur();
+                  }
+                }}
+              >
+                {appTitle}
+              </h1>
+            )}
+            <div className="flex items-center space-x-4">
+              <NavLink to="/" className={({ isActive }) => (isActive ? "navlink active" : "navlink")}>
+                Logs
+              </NavLink>
+              <NavLink to="/models" className={({ isActive }) => (isActive ? "navlink active" : "navlink")}>
+                Models
+              </NavLink>
+              <NavLink to="/activity" className={({ isActive }) => (isActive ? "navlink active" : "navlink")}>
+                Activity
+              </NavLink>
+              <button className="" onClick={toggleTheme}>
+                {isDarkMode ? <RiMoonFill /> : <RiSunFill />}
+              </button>
+              <ConnectionStatusIcon />
             </div>
-          </nav>
+          </div>
+        </nav>
 
-          <main className="mx-auto py-4 px-4">
-            <Routes>
-              <Route path="/" element={<LogViewerPage />} />
-              <Route path="/models" element={<ModelPage />} />
-              <Route path="*" element={<Navigate to="/" replace />} />
-            </Routes>
-          </main>
-        </div>
-      </APIProvider>
+        <main className="flex-1 overflow-auto p-4">
+          <Routes>
+            <Route path="/" element={<LogViewerPage />} />
+            <Route path="/models" element={<ModelPage />} />
+            <Route path="/activity" element={<ActivityPage />} />
+            <Route path="*" element={<Navigate to="/" replace />} />
+          </Routes>
+        </main>
+      </div>
     </Router>
   );
 }

ui/src/components/ConnectionStatus.tsx

@@ -0,0 +1,26 @@
+import { useAPI } from "../contexts/APIProvider";
+import { useMemo } from "react";
+
+const ConnectionStatusIcon = () => {
+  const { connectionStatus } = useAPI();
+
+  const eventStatusColor = useMemo(() => {
+    switch (connectionStatus) {
+      case "connected":
+        return "bg-green-500";
+      case "connecting":
+        return "bg-yellow-500";
+      case "disconnected":
+      default:
+        return "bg-red-500";
+    }
+  }, [connectionStatus]);
+
+  return (
+    <div className="flex items-center" title={`event stream: ${connectionStatus}`}>
+      <span className={`inline-block w-3 h-3 rounded-full ${eventStatusColor} mr-2`}></span>
+    </div>
+  );
+};
+
+export default ConnectionStatusIcon;

ui/src/contexts/APIProvider.tsx

@@ -1,4 +1,5 @@
 import { useRef, createContext, useState, useContext, useEffect, useCallback, useMemo, type ReactNode } from "react";
+import type { ConnectionState } from "../lib/types";
 
 type ModelStatus = "ready" | "starting" | "stopping" | "stopped" | "shutdown" | "unknown";
 const LOG_LENGTH_LIMIT = 1024 * 100; /* 100KB of log data */
@@ -19,30 +20,44 @@ interface APIProviderType {
   enableAPIEvents: (enabled: boolean) => void;
   proxyLogs: string;
   upstreamLogs: string;
+  metrics: Metrics[];
+  connectionStatus: ConnectionState;
 }
+
+interface Metrics {
+  id: number;
+  timestamp: string;
+  model: string;
+  input_tokens: number;
+  output_tokens: number;
+  prompt_per_second: number;
+  tokens_per_second: number;
+  duration_ms: number;
+}
+
 interface LogData {
   source: "upstream" | "proxy";
   data: string;
 }
 interface APIEventEnvelope {
-  type: "modelStatus" | "logData";
+  type: "modelStatus" | "logData" | "metrics";
   data: string;
 }
 
 const APIContext = createContext<APIProviderType | undefined>(undefined);
 type APIProviderProps = {
   children: ReactNode;
+  autoStartAPIEvents?: boolean;
 };
 
-export function APIProvider({ children }: APIProviderProps) {
+export function APIProvider({ children, autoStartAPIEvents = true }: APIProviderProps) {
   const [proxyLogs, setProxyLogs] = useState("");
   const [upstreamLogs, setUpstreamLogs] = useState("");
-  const proxyEventSource = useRef<EventSource | null>(null);
-  const upstreamEventSource = useRef<EventSource | null>(null);
+  const [metrics, setMetrics] = useState<Metrics[]>([]);
+  const [connectionStatus, setConnectionState] = useState<ConnectionState>("disconnected");
   const apiEventSource = useRef<EventSource | null>(null);
 
   const [models, setModels] = useState<Model[]>([]);
-  const modelStatusEventSource = useRef<EventSource | null>(null);
 
   const appendLog = useCallback((newData: string, setter: React.Dispatch<React.SetStateAction<string>>) => {
     setter((prev) => {
@@ -55,6 +70,7 @@ export function APIProvider({ children }: APIProviderProps) {
     if (!enabled) {
       apiEventSource.current?.close();
       apiEventSource.current = null;
+      setMetrics([]);
       return;
     }
 
@@ -62,7 +78,20 @@ export function APIProvider({ children }: APIProviderProps) {
     const initialDelay = 1000; // 1 second
 
     const connect = () => {
+      apiEventSource.current = null;
       const eventSource = new EventSource("/api/events");
+      setConnectionState("connecting");
+
+      eventSource.onopen = () => {
+        // clear everything out on connect to keep things in sync
+        setProxyLogs("");
+        setUpstreamLogs("");
+        setMetrics([]); // clear metrics on reconnect
+        setModels([]); // clear models on reconnect
+        apiEventSource.current = eventSource;
+        retryCount = 0;
+        setConnectionState("connected");
+      };
 
       eventSource.onmessage = (e: MessageEvent) => {
         try {
@@ -71,11 +100,17 @@ export function APIProvider({ children }: APIProviderProps) {
             case "modelStatus":
               {
                 const models = JSON.parse(message.data) as Model[];
+
+                // sort models by name and id
+                models.sort((a, b) => {
+                  return (a.name + a.id).localeCompare(b.name + b.id);
+                });
+
                 setModels(models);
               }
               break;
 
-            case "logData": {
+            case "logData":
               const logData = JSON.parse(message.data) as LogData;
               switch (logData.source) {
                 case "proxy":
@@ -85,32 +120,43 @@ export function APIProvider({ children }: APIProviderProps) {
                   appendLog(logData.data, setUpstreamLogs);
                   break;
               }
-            }
+              break;
+
+            case "metrics":
+              {
+                const newMetrics = JSON.parse(message.data) as Metrics[];
+                setMetrics((prevMetrics) => {
+                  return [...newMetrics, ...prevMetrics];
+                });
+              }
+              break;
           }
         } catch (err) {
           console.error(e.data, err);
         }
       };
+
       eventSource.onerror = () => {
         eventSource.close();
         retryCount++;
         const delay = Math.min(initialDelay * Math.pow(2, retryCount - 1), 5000);
+        setConnectionState("disconnected");
         setTimeout(connect, delay);
       };
-
-      apiEventSource.current = eventSource;
     };
 
     connect();
   }, []);
 
   useEffect(() => {
+    if (autoStartAPIEvents) {
+      enableAPIEvents(true);
+    }
+
     return () => {
-      proxyEventSource.current?.close();
-      upstreamEventSource.current?.close();
-      modelStatusEventSource.current?.close();
+      enableAPIEvents(false);
     };
-  }, []);
+  }, [enableAPIEvents, autoStartAPIEvents]);
 
   const listModels = useCallback(async (): Promise<Model[]> => {
     try {
@@ -163,8 +209,10 @@ export function APIProvider({ children }: APIProviderProps) {
       enableAPIEvents,
       proxyLogs,
       upstreamLogs,
+      metrics,
+      connectionStatus,
     }),
-    [models, listModels, unloadAllModels, loadModel, enableAPIEvents, proxyLogs, upstreamLogs]
+    [models, listModels, unloadAllModels, loadModel, enableAPIEvents, proxyLogs, upstreamLogs, metrics]
   );
 
   return <APIContext.Provider value={value}>{children}</APIContext.Provider>;

ui/src/contexts/ThemeProvider.tsx

@@ -1,9 +1,18 @@
-import { createContext, useContext, useEffect, type ReactNode } from "react";
+import { createContext, useContext, useEffect, type ReactNode, useMemo, useState } from "react";
 import { usePersistentState } from "../hooks/usePersistentState";
+import type { ConnectionState } from "../lib/types";
 
+type ScreenWidth = "xs" | "sm" | "md" | "lg" | "xl" | "2xl";
 type ThemeContextType = {
   isDarkMode: boolean;
+  screenWidth: ScreenWidth;
+  isNarrow: boolean;
   toggleTheme: () => void;
+
+  // for managing the window title and connection state information
+  appTitle: string;
+  setAppTitle: (title: string) => void;
+  setConnectionState: (state: ConnectionState) => void;
 };
 
 const ThemeContext = createContext<ThemeContextType | undefined>(undefined);
@@ -13,15 +22,70 @@ type ThemeProviderProps = {
 };
 
 export function ThemeProvider({ children }: ThemeProviderProps) {
+  const [appTitle, setAppTitle] = usePersistentState("app-title", "llama-swap");
+  const [connectionState, setConnectionState] = useState<ConnectionState>("disconnected");
+
+  /**
+   * Set the document.title with informative information
+   */
+  useEffect(() => {
+    const connectionIcon = connectionState === "connecting" ? "🟡" : connectionState === "connected" ? "🟢" : "🔴";
+    document.title = connectionIcon + " " + appTitle; // Set initial title
+  }, [appTitle, connectionState]);
+
   const [isDarkMode, setIsDarkMode] = usePersistentState<boolean>("theme", false);
+  const [screenWidth, setScreenWidth] = useState<ScreenWidth>("md"); // Default to md
+
+  // matches tailwind classes
+  // https://tailwindcss.com/docs/responsive-design
+  useEffect(() => {
+    const checkInnerWidth = () => {
+      const innerWidth = window.innerWidth;
+      if (innerWidth < 640) {
+        setScreenWidth("xs");
+      } else if (innerWidth < 768) {
+        setScreenWidth("sm");
+      } else if (innerWidth < 1024) {
+        setScreenWidth("md");
+      } else if (innerWidth < 1280) {
+        setScreenWidth("lg");
+      } else if (innerWidth < 1536) {
+        setScreenWidth("xl");
+      } else {
+        setScreenWidth("2xl");
+      }
+    };
+
+    checkInnerWidth();
+    window.addEventListener("resize", checkInnerWidth);
+
+    return () => window.removeEventListener("resize", checkInnerWidth);
+  }, []);
 
   useEffect(() => {
     document.documentElement.setAttribute("data-theme", isDarkMode ? "dark" : "light");
   }, [isDarkMode]);
 
   const toggleTheme = () => setIsDarkMode((prev) => !prev);
+  const isNarrow = useMemo(() => {
+    return screenWidth === "xs" || screenWidth === "sm" || screenWidth === "md";
+  }, [screenWidth]);
 
-  return <ThemeContext.Provider value={{ isDarkMode, toggleTheme }}>{children}</ThemeContext.Provider>;
+  return (
+    <ThemeContext.Provider
+      value={{
+        isDarkMode,
+        toggleTheme,
+        screenWidth,
+        isNarrow,
+        appTitle,
+        setAppTitle,
+        setConnectionState,
+      }}
+    >
+      {children}
+    </ThemeContext.Provider>
+  );
 }
 
 export function useTheme(): ThemeContextType {

ui/src/lib/Utils.ts

@@ -1,18 +0,0 @@
-export function processEvalTimes(text: string) {
-  const lines = text.match(/^ *eval time.*$/gm) || [];
-
-  let totalTokens = 0;
-  let totalTime = 0;
-
-  lines.forEach((line) => {
-    const tokensMatch = line.match(/\/\s*(\d+)\s*tokens/);
-    const timeMatch = line.match(/=\s*(\d+\.\d+)\s*ms/);
-
-    if (tokensMatch) totalTokens += parseFloat(tokensMatch[1]);
-    if (timeMatch) totalTime += parseFloat(timeMatch[1]);
-  });
-
-  const avgTokensPerSecond = totalTime > 0 ? totalTokens / (totalTime / 1000) : 0;
-
-  return [lines.length, totalTokens, Math.round(avgTokensPerSecond * 100) / 100];
-}

ui/src/lib/types.ts

@@ -0,0 +1 @@
+export type ConnectionState = "connected" | "connecting" | "disconnected";

ui/src/main.tsx

@@ -3,11 +3,14 @@ import { createRoot } from "react-dom/client";
 import "./index.css";
 import App from "./App.tsx";
 import { ThemeProvider } from "./contexts/ThemeProvider";
+import { APIProvider } from "./contexts/APIProvider";
 
 createRoot(document.getElementById("root")!).render(
   <StrictMode>
     <ThemeProvider>
-      <App />
+      <APIProvider>
+        <App />
+      </APIProvider>
     </ThemeProvider>
   </StrictMode>
 );

ui/src/pages/Activity.tsx

@@ -0,0 +1,66 @@
+import { useMemo } from "react";
+import { useAPI } from "../contexts/APIProvider";
+
+const formatTimestamp = (timestamp: string): string => {
+  return new Date(timestamp).toLocaleString();
+};
+
+const formatSpeed = (speed: number): string => {
+  return speed < 0 ? "unknown" : speed.toFixed(2) + " t/s";
+};
+
+const formatDuration = (ms: number): string => {
+  return (ms / 1000).toFixed(2) + "s";
+};
+
+const ActivityPage = () => {
+  const { metrics } = useAPI();
+  const sortedMetrics = useMemo(() => {
+    return [...metrics].sort((a, b) => b.id - a.id);
+  }, [metrics]);
+
+  return (
+    <div className="p-6">
+      <h1 className="text-2xl font-bold mb-4">Activity</h1>
+
+      {metrics.length === 0 ? (
+        <div className="text-center py-8">
+          <p className="text-gray-600">No metrics data available</p>
+        </div>
+      ) : (
+        <div className="overflow-x-auto">
+          <table className="min-w-full divide-y">
+            <thead>
+              <tr>
+                <th className="px-4 py-3 text-left text-xs font-medium uppercase tracking-wider">Id</th>
+                <th className="px-6 py-3 text-left text-xs font-medium uppercase tracking-wider">Timestamp</th>
+                <th className="px-6 py-3 text-left text-xs font-medium uppercase tracking-wider">Model</th>
+                <th className="px-6 py-3 text-left text-xs font-medium uppercase tracking-wider">Input Tokens</th>
+                <th className="px-6 py-3 text-left text-xs font-medium uppercase tracking-wider">Output Tokens</th>
+                <th className="px-6 py-3 text-left text-xs font-medium uppercase tracking-wider">Prompt Processing</th>
+                <th className="px-6 py-3 text-left text-xs font-medium uppercase tracking-wider">Generation Speed</th>
+                <th className="px-6 py-3 text-left text-xs font-medium uppercase tracking-wider">Duration</th>
+              </tr>
+            </thead>
+            <tbody className="divide-y">
+              {sortedMetrics.map((metric) => (
+                <tr key={`metric_${metric.id}`}>
+                  <td className="px-4 py-4 whitespace-nowrap text-sm">{metric.id + 1 /* un-zero index */}</td>
+                  <td className="px-6 py-4 whitespace-nowrap text-sm">{formatTimestamp(metric.timestamp)}</td>
+                  <td className="px-6 py-4 whitespace-nowrap text-sm">{metric.model}</td>
+                  <td className="px-6 py-4 whitespace-nowrap text-sm">{metric.input_tokens.toLocaleString()}</td>
+                  <td className="px-6 py-4 whitespace-nowrap text-sm">{metric.output_tokens.toLocaleString()}</td>
+                  <td className="px-6 py-4 whitespace-nowrap text-sm">{formatSpeed(metric.prompt_per_second)}</td>
+                  <td className="px-6 py-4 whitespace-nowrap text-sm">{formatSpeed(metric.tokens_per_second)}</td>
+                  <td className="px-6 py-4 whitespace-nowrap text-sm">{formatDuration(metric.duration_ms)}</td>
+                </tr>
+              ))}
+            </tbody>
+          </table>
+        </div>
+      )}
+    </div>
+  );
+};
+
+export default ActivityPage;

ui/src/pages/LogViewer.tsx

@@ -1,22 +1,38 @@
 import { useState, useEffect, useRef, useMemo, useCallback } from "react";
 import { useAPI } from "../contexts/APIProvider";
 import { usePersistentState } from "../hooks/usePersistentState";
+import { Panel, PanelGroup, PanelResizeHandle } from "react-resizable-panels";
+import {
+  RiTextWrap,
+  RiAlignJustify,
+  RiFontSize,
+  RiMenuSearchLine,
+  RiMenuSearchFill,
+  RiCloseCircleFill,
+} from "react-icons/ri";
+import { useTheme } from "../contexts/ThemeProvider";
 
 const LogViewer = () => {
-  const { proxyLogs, upstreamLogs, enableAPIEvents } = useAPI();
-
-  useEffect(() => {
-    enableAPIEvents(true);
-    return () => {
-      enableAPIEvents(false);
-    };
-  }, []);
+  const { proxyLogs, upstreamLogs } = useAPI();
+  const { isNarrow } = useTheme();
+  const direction = isNarrow ? "vertical" : "horizontal";
 
   return (
-    <div className="flex flex-col gap-5" style={{ height: "calc(100vh - 125px)" }}>
-      <LogPanel id="proxy" title="Proxy Logs" logData={proxyLogs} />
-      <LogPanel id="upstream" title="Upstream Logs" logData={upstreamLogs} />
-    </div>
+    <PanelGroup direction={direction} className="gap-2" autoSaveId="logviewer-panel-group">
+      <Panel id="proxy" defaultSize={50} minSize={5} maxSize={100} collapsible={true}>
+        <LogPanel id="proxy" title="Proxy Logs" logData={proxyLogs} />
+      </Panel>
+      <PanelResizeHandle
+        className={
+          direction === "horizontal"
+            ? "w-2 h-full bg-primary hover:bg-success transition-colors rounded"
+            : "w-full h-2 bg-primary hover:bg-success transition-colors rounded"
+        }
+      />
+      <Panel id="upstream" defaultSize={50} minSize={5} maxSize={100} collapsible={true}>
+        <LogPanel id="upstream" title="Upstream Logs" logData={upstreamLogs} />
+      </Panel>
+    </PanelGroup>
   );
 };
 
@@ -24,17 +40,15 @@ interface LogPanelProps {
   id: string;
   title: string;
   logData: string;
-  className?: string;
 }
-
-export const LogPanel = ({ id, title, logData, className }: LogPanelProps) => {
-  const [isCollapsed, setIsCollapsed] = usePersistentState(`logPanel-${id}-isCollapsed`, false);
+export const LogPanel = ({ id, title, logData }: LogPanelProps) => {
   const [filterRegex, setFilterRegex] = useState("");
   const [fontSize, setFontSize] = usePersistentState<"xxs" | "xs" | "small" | "normal">(
     `logPanel-${id}-fontSize`,
     "normal"
   );
   const [wrapText, setTextWrap] = usePersistentState(`logPanel-${id}-wrapText`, false);
+  const [showFilter, setShowFilter] = usePersistentState(`logPanel-${id}-showFilter`, false);
 
   const textWrapClass = useMemo(() => {
     return wrapText ? "whitespace-pre-wrap" : "whitespace-pre";
@@ -55,6 +69,19 @@ export const LogPanel = ({ id, title, logData, className }: LogPanelProps) => {
     });
   }, []);
 
+  const toggleWrapText = useCallback(() => {
+    setTextWrap((prev) => !prev);
+  }, []);
+
+  const toggleFilter = useCallback(() => {
+    if (showFilter) {
+      setShowFilter(false);
+      setFilterRegex(""); // Clear filter when closing
+    } else {
+      setShowFilter(true);
+    }
+  }, [filterRegex, setFilterRegex, showFilter]);
+
   const fontSizeClass = useMemo(() => {
     switch (fontSize) {
       case "xxs":
@@ -88,56 +115,47 @@ export const LogPanel = ({ id, title, logData, className }: LogPanelProps) => {
   }, [filteredLogs]);
 
   return (
-    <div
-      className={`bg-surface border border-border rounded-lg overflow-hidden flex flex-col ${
-        !isCollapsed && "h-full"
-      } ${className || ""}`}
-    >
+    <div className="bg-surface border border-border rounded-lg overflow-hidden flex flex-col h-full">
       <div className="p-4 border-b border-border bg-secondary">
-        <div className="flex flex-col md:flex-row md:items-center md:justify-between gap-4">
-          {/* Title - Always full width on mobile, normal on desktop */}
-          <div className="w-full md:w-auto" onClick={() => setIsCollapsed(!isCollapsed)}>
-            <h3 className="m-0 text-lg">{title}</h3>
+        <div className="flex items-center justify-between">
+          <h3 className="m-0 text-lg p-0">{title}</h3>
+
+          <div className="flex gap-2 items-center">
+            <button className="btn" onClick={toggleFontSize}>
+              <RiFontSize />
+            </button>
+            <button className="btn" onClick={toggleWrapText}>
+              {wrapText ? <RiTextWrap /> : <RiAlignJustify />}
+            </button>
+            <button className="btn" onClick={toggleFilter}>
+              {showFilter ? <RiMenuSearchFill /> : <RiMenuSearchLine />}
+            </button>
           </div>
+        </div>
 
-          <div className="flex flex-col sm:flex-row gap-4 w-full md:w-auto">
-            {/* Sizing Buttons - Stacks vertically on mobile */}
-            <div className="flex flex-wrap gap-2">
-              <button className="btn" onClick={toggleFontSize}>
-                font: {fontSize}
-              </button>
-              <button className="btn" onClick={() => setTextWrap((prev) => !prev)}>
-                {wrapText ? "wrap" : "wrap off"}
-              </button>
-            </div>
-
-            {/* Filtering Options - Full width on mobile, normal on desktop */}
-            <div className="flex flex-1 min-w-0 gap-2">
+        {/* Filtering Options - Full width on mobile, normal on desktop */}
+        {showFilter && (
+          <div className="mt-2 w-full">
+            <div className="flex gap-2 items-center w-full">
               <input
                 type="text"
-                className="flex-1 min-w-[120px] text-sm border p-2 rounded"
+                className="w-full text-sm border p-2 rounded"
                 placeholder="Filter logs..."
                 value={filterRegex}
                 onChange={(e) => setFilterRegex(e.target.value)}
               />
-              <button className="btn" onClick={() => setFilterRegex("")}>
-                Clear
+              <button className="pl-2" onClick={() => setFilterRegex("")}>
+                <RiCloseCircleFill size="24" />
               </button>
             </div>
           </div>
-        </div>
+        )}
+      </div>
+      <div className="bg-background font-mono text-sm flex-1 overflow-hidden">
+        <pre ref={preTagRef} className={`${textWrapClass} ${fontSizeClass} h-full overflow-auto p-4`}>
+          {filteredLogs}
+        </pre>
       </div>
-
-      {!isCollapsed && (
-        <div className="flex-1 bg-background font-mono text-sm p-3 overflow-hidden">
-          <pre
-            ref={preTagRef}
-            className={`h-full p-4 overflow-y-auto whitespace-pre min-h-0 ${textWrapClass} ${fontSizeClass}`}
-          >
-            {filteredLogs}
-          </pre>
-        </div>
-      )}
     </div>
   );
 };

ui/src/pages/Models.tsx

@@ -1,25 +1,51 @@
-import { useState, useEffect, useCallback, useMemo } from "react";
+import { useState, useCallback, useMemo } from "react";
 import { useAPI } from "../contexts/APIProvider";
 import { LogPanel } from "./LogViewer";
-import { processEvalTimes } from "../lib/Utils";
 import { usePersistentState } from "../hooks/usePersistentState";
+import { Panel, PanelGroup, PanelResizeHandle } from "react-resizable-panels";
+import { useTheme } from "../contexts/ThemeProvider";
+import { RiEyeFill, RiEyeOffFill, RiStopCircleLine, RiSwapBoxFill } from "react-icons/ri";
 
 export default function ModelsPage() {
-  const { models, unloadAllModels, loadModel, upstreamLogs, enableAPIEvents } = useAPI();
+  const { isNarrow } = useTheme();
+  const direction = isNarrow ? "vertical" : "horizontal";
+  const { upstreamLogs } = useAPI();
+
+  return (
+    <PanelGroup direction={direction} className="gap-2" autoSaveId={"models-panel-group"}>
+      <Panel id="models" defaultSize={50} minSize={isNarrow ? 0 : 25} maxSize={100} collapsible={isNarrow}>
+        <ModelsPanel />
+      </Panel>
+
+      <PanelResizeHandle
+        className={
+          direction === "horizontal"
+            ? "w-2 h-full bg-primary hover:bg-success transition-colors rounded"
+            : "w-full h-2 bg-primary hover:bg-success transition-colors rounded"
+        }
+      />
+      <Panel collapsible={true} defaultSize={50} minSize={0}>
+        <div className="flex flex-col h-full space-y-4">
+          {direction === "horizontal" && <StatsPanel />}
+          <div className="flex-1 min-h-0">
+            <LogPanel id="modelsupstream" title="Upstream Logs" logData={upstreamLogs} />
+          </div>
+        </div>
+      </Panel>
+    </PanelGroup>
+  );
+}
+
+function ModelsPanel() {
+  const { models, loadModel, unloadAllModels } = useAPI();
   const [isUnloading, setIsUnloading] = useState(false);
   const [showUnlisted, setShowUnlisted] = usePersistentState("showUnlisted", true);
+  const [showIdorName, setShowIdorName] = usePersistentState<"id" | "name">("showIdorName", "id"); // true = show ID, false = show name
 
   const filteredModels = useMemo(() => {
     return models.filter((model) => showUnlisted || !model.unlisted);
   }, [models, showUnlisted]);
 
-  useEffect(() => {
-    enableAPIEvents(true);
-    return () => {
-      enableAPIEvents(false);
-    };
-  }, []);
-
   const handleUnloadAllModels = useCallback(async () => {
     setIsUnloading(true);
     try {
@@ -27,98 +53,120 @@ export default function ModelsPage() {
     } catch (e) {
       console.error(e);
     } finally {
-      // at least give it a second to show the unloading message
       setTimeout(() => {
         setIsUnloading(false);
       }, 1000);
     }
-  }, []);
+  }, [unloadAllModels]);
 
-  const [totalLines, totalTokens, avgTokensPerSecond] = useMemo(() => {
-    return processEvalTimes(upstreamLogs);
-  }, [upstreamLogs]);
+  const toggleIdorName = useCallback(() => {
+    setShowIdorName((prev) => (prev === "name" ? "id" : "name"));
+  }, [showIdorName]);
 
   return (
-    <div>
-      <div className="flex flex-col md:flex-row gap-4">
-        {/* Left Column */}
-        <div className="w-full md:w-1/2 flex items-top">
-          <div className="card w-full">
-            <h2 className="">Models</h2>
-            <div className="flex justify-between">
-              <button className="btn" onClick={() => setShowUnlisted(!showUnlisted)} style={{ lineHeight: "1.2" }}>
-                {showUnlisted ? "🟢 unlisted" : "⚫️ unlisted"}
-              </button>
-              <button className="btn" onClick={handleUnloadAllModels} disabled={isUnloading}>
-                {isUnloading ? "Stopping ..." : "Stop All"}
-              </button>
-            </div>
+    <div className="card h-full flex flex-col">
+      <div className="shrink-0">
+        <h2>Models</h2>
+        <div className="flex justify-between">
+          <div className="flex gap-2">
+            <button className="btn flex items-center gap-2" onClick={toggleIdorName} style={{ lineHeight: "1.2" }}>
+              <RiSwapBoxFill /> {showIdorName === "id" ? "ID" : "Name"}
+            </button>
 
-            <table className="w-full mt-4">
-              <thead>
-                <tr className="border-b border-primary">
-                  <th className="text-left p-2">Name</th>
-                  <th className="text-left p-2"></th>
-                  <th className="text-left p-2">State</th>
-                </tr>
-              </thead>
-              <tbody>
-                {filteredModels.map((model) => (
-                  <tr key={model.id} className="border-b hover:bg-secondary-hover border-border">
-                    <td className="p-2">
-                      <a href={`/upstream/${model.id}/`} className="underline" target="_blank">
-                        {model.name !== "" ? model.name : model.id}
-                      </a>
-                      {model.description != "" && (
-                        <p>
-                          <em>{model.description}</em>
-                        </p>
-                      )}
-                    </td>
-                    <td className="p-2 w-[50px]">
-                      <button
-                        className="btn btn--sm"
-                        disabled={model.state !== "stopped"}
-                        onClick={() => loadModel(model.id)}
-                      >
-                        Load
-                      </button>
-                    </td>
-                    <td className="p-2 w-[75px]">
-                      <span className={`status status--${model.state}`}>{model.state}</span>
-                    </td>
-                  </tr>
-                ))}
-              </tbody>
-            </table>
+            <button
+              className="btn flex items-center gap-2"
+              onClick={() => setShowUnlisted(!showUnlisted)}
+              style={{ lineHeight: "1.2" }}
+            >
+              {showUnlisted ? <RiEyeFill /> : <RiEyeOffFill />} unlisted
+            </button>
           </div>
+          <button className="btn flex items-center gap-2" onClick={handleUnloadAllModels} disabled={isUnloading}>
+            <RiStopCircleLine size="24" /> {isUnloading ? "Unloading..." : "Unload"}
+          </button>
         </div>
+      </div>
 
-        {/* Right Column */}
-        <div className="w-full md:w-1/2 flex flex-col" style={{ height: "calc(100vh - 125px)" }}>
-          <div className="card mb-4 min-h-[250px]">
-            <h2>Log Stats</h2>
-            <p className="italic my-2">note: eval logs from llama-server</p>
-            <table className="w-full border border-gray-200">
-              <tbody>
-                <tr className="border-b border-gray-200">
-                  <td className="py-2 px-4 font-medium border-r border-gray-200">Requests</td>
-                  <td className="py-2 px-4 text-right">{totalLines}</td>
-                </tr>
-                <tr className="border-b border-gray-200">
-                  <td className="py-2 px-4 font-medium border-r border-gray-200">Total Tokens Generated</td>
-                  <td className="py-2 px-4 text-right">{totalTokens}</td>
-                </tr>
-                <tr>
-                  <td className="py-2 px-4 font-medium border-r border-gray-200">Average Tokens/Second</td>
-                  <td className="py-2 px-4 text-right">{avgTokensPerSecond}</td>
-                </tr>
-              </tbody>
-            </table>
-          </div>
-
-          <LogPanel id="modelsupstream" title="Upstream Logs" logData={upstreamLogs} />
-        </div>
+      <div className="flex-1 overflow-y-auto">
+        <table className="w-full">
+          <thead className="sticky top-0 bg-card z-10">
+            <tr className="border-b border-primary bg-surface">
+              <th className="text-left p-2">{showIdorName === "id" ? "Model ID" : "Name"}</th>
+              <th className="text-left p-2"></th>
+              <th className="text-left p-2">State</th>
+            </tr>
+          </thead>
+          <tbody>
+            {filteredModels.map((model) => (
+              <tr key={model.id} className="border-b hover:bg-secondary-hover border-border">
+                <td className={`p-2 ${model.unlisted ? "text-txtsecondary" : ""}`}>
+                  <a href={`/upstream/${model.id}/`} className={`underline`} target="_blank">
+                    {showIdorName === "id" ? model.id : model.name !== "" ? model.name : model.id}
+                  </a>
+                  {model.description !== "" && (
+                    <p className={model.unlisted ? "text-opacity-70" : ""}>
+                      <em>{model.description}</em>
+                    </p>
+                  )}
+                </td>
+                <td className="p-2 w-[50px]">
+                  <button
+                    className="btn btn--sm"
+                    disabled={model.state !== "stopped"}
+                    onClick={() => loadModel(model.id)}
+                  >
+                    Load
+                  </button>
+                </td>
+                <td className="p-2 w-[75px]">
+                  <span className={`status status--${model.state}`}>{model.state}</span>
+                </td>
+              </tr>
+            ))}
+          </tbody>
+        </table>
+      </div>
+    </div>
+  );
+}
+
+function StatsPanel() {
+  const { metrics } = useAPI();
+
+  const [totalRequests, totalInputTokens, totalOutputTokens, avgTokensPerSecond] = useMemo(() => {
+    const totalRequests = metrics.length;
+    if (totalRequests === 0) {
+      return [0, 0, 0];
+    }
+    const totalInputTokens = metrics.reduce((sum, m) => sum + m.input_tokens, 0);
+    const totalOutputTokens = metrics.reduce((sum, m) => sum + m.output_tokens, 0);
+    const avgTokensPerSecond = (metrics.reduce((sum, m) => sum + m.tokens_per_second, 0) / totalRequests).toFixed(2);
+    return [totalRequests, totalInputTokens, totalOutputTokens, avgTokensPerSecond];
+  }, [metrics]);
+
+  return (
+    <div className="card">
+      <div className="rounded-lg overflow-hidden border border-gray-200">
+        <table className="w-full">
+          <tbody>
+            <tr>
+              <th className="p-2 font-medium border-b border-gray-200 text-right">Requests</th>
+              <th className="p-2 font-medium border-l border-b border-gray-200 text-right">Processed</th>
+              <th className="p-2 font-medium border-l border-b border-gray-200 text-right">Generated</th>
+              <th className="p-2 font-medium border-l border-b border-gray-200 text-right">Tokens/Sec</th>
+            </tr>
+            <tr>
+              <td className="p-2 text-right border-r border-gray-200">{totalRequests}</td>
+              <td className="p-2 text-right border-r border-gray-200">
+                {new Intl.NumberFormat().format(totalInputTokens)}
+              </td>
+              <td className="p-2 text-right border-r border-gray-200">
+                {new Intl.NumberFormat().format(totalOutputTokens)}
+              </td>
+              <td className="p-2 text-right">{avgTokensPerSecond}</td>
+            </tr>
+          </tbody>
+        </table>
       </div>
     </div>
   );